On maverick the same issue.
with only wlan0 it disconnects frequently when there is network traffic .
If no or low traffic the connection seems to be stable.

with wicd the problem not occurs (in same conditions, same place, same net).


Dec 13 10:04:40 luca-laptop NetworkManagerDispatcher: lo is down
Dec 13 10:04:40 luca-laptop kernel: [   45.704994] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
Dec 13 10:04:41 luca-laptop kernel: [   46.500174] hda-intel: IRQ timing workaround is activated for card #1. Suggest a bigger bdl_pos_adj.
Dec 13 10:04:59 luca-laptop nautilus: [N-A] Nautilus-Actions Tracker 2.30.2 initializing...
Dec 13 10:04:59 luca-laptop nautilus: [N-A] Nautilus-Actions Menu Extender 2.30.2 initializing...
Dec 13 10:04:59 luca-laptop kernel: [   65.114067] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Dec 13 10:05:00 luca-laptop kernel: [   65.397739] Intel AES-NI instructions are not detected.
Dec 13 10:05:00 luca-laptop kernel: [   65.554359] padlock: VIA PadLock not detected.
Dec 13 10:05:10 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:05:10 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID EMC
Dec 13 10:05:10 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:05:10 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:05:11 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:05:11 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:05:23 luca-laptop kernel: [   87.472647] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:05:23 luca-laptop kernel: [   87.475537] cfg80211: World regulatory domain updated:
Dec 13 10:05:23 luca-laptop kernel: [   87.475539]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:05:23 luca-laptop kernel: [   87.475541]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:05:23 luca-laptop kernel: [   87.475544]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:05:23 luca-laptop kernel: [   87.475546]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:05:23 luca-laptop kernel: [   87.475548]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:05:23 luca-laptop kernel: [   87.475550]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:05:24 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID Alice-36687582
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:05:34 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:05:44 luca-laptop sudo: pam_sm_authenticate: Called
Dec 13 10:05:44 luca-laptop sudo: pam_sm_authenticate: username = [luca]
Dec 13 10:07:15 luca-laptop kernel: [  199.752691] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:07:15 luca-laptop kernel: [  199.756061] cfg80211: World regulatory domain updated:
Dec 13 10:07:15 luca-laptop kernel: [  199.756064]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:07:15 luca-laptop kernel: [  199.756067]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:07:15 luca-laptop kernel: [  199.756069]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:07:15 luca-laptop kernel: [  199.756072]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:07:15 luca-laptop kernel: [  199.756074]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:07:15 luca-laptop kernel: [  199.756077]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:07:32 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:08:20 luca-laptop kernel: [  264.112571] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:08:20 luca-laptop kernel: [  264.116622] cfg80211: World regulatory domain updated:
Dec 13 10:08:20 luca-laptop kernel: [  264.116625]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:08:20 luca-laptop kernel: [  264.116628]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:20 luca-laptop kernel: [  264.116630]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:20 luca-laptop kernel: [  264.116633]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:20 luca-laptop kernel: [  264.116635]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:20 luca-laptop kernel: [  264.116638]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:28 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:08:28 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID Alice-36687582
Dec 13 10:08:28 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:08:28 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:08:28 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:08:29 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:08:41 luca-laptop kernel: [  285.592748] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:08:41 luca-laptop kernel: [  285.600935] cfg80211: World regulatory domain updated:
Dec 13 10:08:41 luca-laptop kernel: [  285.600942]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:08:41 luca-laptop kernel: [  285.600951]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:41 luca-laptop kernel: [  285.600958]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:41 luca-laptop kernel: [  285.600966]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:41 luca-laptop kernel: [  285.600972]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:41 luca-laptop kernel: [  285.600979]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:08:58 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:09:26 luca-laptop kernel: [  330.290149] CE: hpet increased min_delta_ns to 7500 nsec
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID Alice-36687582
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:09:53 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:10:04 luca-laptop kernel: [  368.472814] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:10:04 luca-laptop kernel: [  368.481537] cfg80211: World regulatory domain updated:
Dec 13 10:10:04 luca-laptop kernel: [  368.481544]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:10:04 luca-laptop kernel: [  368.481552]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:10:04 luca-laptop kernel: [  368.481560]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:10:04 luca-laptop kernel: [  368.481567]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:10:04 luca-laptop kernel: [  368.481574]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:10:04 luca-laptop kernel: [  368.481581]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:10:21 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID Alice-36687582
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:11:16 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:24:47 luca-laptop kernel: [ 1250.798874] process `skype' is using obsolete setsockopt SO_BSDCOMPAT
Dec 13 10:25:18 luca-laptop kernel: [ 1282.771676] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779571] cfg80211: World regulatory domain updated:
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779578]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779586]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779594]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779602]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779609]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:25:18 luca-laptop kernel: [ 1282.779615]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:25:35 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID Alice-36687582
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:26:30 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:27:37 luca-laptop kernel: [ 1421.410315] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:27:37 luca-laptop kernel: [ 1421.417997] cfg80211: World regulatory domain updated:
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418004]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418012]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418020]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418027]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418034]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:27:37 luca-laptop kernel: [ 1421.418041]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:27:54 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:28:26 luca-laptop kernel: [ 1470.727700] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735859] cfg80211: World regulatory domain updated:
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735866]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735874]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735882]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735889]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735896]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:28:26 luca-laptop kernel: [ 1470.735903]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID EMC
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:28:57 luca-laptop NetworkManagerDispatcher: Completed network profiles settings
Dec 13 10:30:41 luca-laptop kernel: [ 1605.610224] cfg80211: Calling CRDA to update world regulatory domain
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618934] cfg80211: World regulatory domain updated:
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618941]     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618950]     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618957]     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618964]     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618971]     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:30:41 luca-laptop kernel: [ 1605.618978]     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Dec 13 10:30:58 luca-laptop NetworkManagerDispatcher: wlan0 is down
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: wlan0 is up (wlan0 up)
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: Found IP 192.168.1.177 ESSID EMC
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: Profile has not changed: home
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: Calling system network settings
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: Calling user network settings for all logged users
Dec 13 10:31:24 luca-laptop NetworkManagerDispatcher: Completed network profiles settings