Bluetooth HFP/HSP profile doesn't work in 18.04

[Christopher Berner]

Hardware: Bose QC35 II

When selecting the A2DP Sink profile these headphones work fine. However, with HSP/HFP selected neither the output nor the microphone work. The headphones will periodically say "Call from" and then break off, and also you can hear a low grade crackling like line noise in them the rest of the time.

Potentially relevant logs:
dmesg (the second message is repeated frequently):
[ 68.288408] input: 2C:41:A1:80:A1:C4 as /devices/virtual/input/input21
[ 78.575027] Bluetooth: hci0: last event is not cmd complete (0x0f)

Originally, I got an error like the following from ("journalctl -u bluetooth"), but then ran "rfkill unblock bluetooth" which seems to have fixed it:
May 13 15:58:02 skylake bluetoothd[1023]: Failed to set mode: Blocked through rfkill (0x12)
May 13 15:58:19 skylake bluetoothd[1023]: Failed to set mode: Blocked through rfkill (0x12)
May 13 16:00:41 skylake bluetoothd[1023]: Unable to get io data for Headset Voice gateway: getpeername: Transport endpoint is not connected (107)
May 13 16:00:41 skylake bluetoothd[1023]: Unable to get io data for Phone Book Access: getpeername: Transport endpoint is not connected (107)

What additional information would be useful to debug this?

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: bluez 5.48-0ubuntu3
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sun May 13 16:33:13 2018
InstallationDate: Installed on 2018-05-13 (0 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
InterestingModules: rfcomm bnep btusb bluetooth
MachineType: System manufacturer System Product Name
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=1
SourcePackage: bluez
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/10/2017
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 3406
dmi.board.asset.tag: Default string
dmi.board.name: Z170I PRO GAMING
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr3406:bd07/10/2017:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnZ170IPROGAMING:rvrRevX.0x:cvnDefaultstring:ct3:cvrDefaultstring:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer
hciconfig:
 hci0: Type: Primary Bus: USB
  BD Address: C8:FF:28:31:68:E4 ACL MTU: 1024:8 SCO MTU: 50:8
  UP RUNNING PSCAN ISCAN INQUIRY
  RX bytes:19479 acl:97 sco:0 events:730 errors:0
  TX bytes:8355 acl:99 sco:3 commands:148 errors:0

[Daniel van Vugt (vanvugt)]

HSP/HFP not working is bug 1768625.

And Bose devices spuriously reporting "call from" etc is bug 1553669.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.