Same problem here:
Laptop ASUS z53sv, with wi-fi module iwl4965, Ubuntu 11.10 (worked fine ultil ubuntu 11.04)
Wifi very slow with router at 802.11B/N. When disabled 802.11B/N and force only 802.11B, wireless came back to normal.
Same problem here:
Laptop ASUS z53sv, with wi-fi module iwl4965, Ubuntu 11.10 (worked fine ultil ubuntu 11.04)
Wifi very slow with router at 802.11B/N. When disabled 802.11B/N and force only 802.11B, wireless came back to normal.