No sound when connecting Sennheiser M2 AEBT for the first time since Fedora 35 upgrade

[Julian Sikorski <belegdol@xxxxxxxxx>]

Hello,

since I upgraded to Fedora 35, am having the following issue with my 
Sennheiser M2 AEBT headphones: upon first connection, the audio will not 
play. I have to go to gnome-control-center, disconnect and reconnect the 
headset, then audio plays normally. The following can be found in the log:

Nov 20 12:48:34 snowball3 kernel: input: MOMENTUM M2 AEBT (AVRCP) as 
/devices/virtual/input/input19

Nov 20 12:48:35 snowball3 bluetoothd[10741]: 
src/service.c:btd_service_connect() a2dp-sink profile connect failed for 
00:1B:66:81:8D:76: Device or resource busy

Nov 20 12:48:35 snowball3 bluetoothd[10741]: 
profiles/audio/avdtp.c:avdtp_parse_rej() OPEN request rejected: Bad 
State (49)

Nov 20 12:48:35 snowball3 wireplumber[1924]: failed to switch codec 
(-19), setting fallback profile

Nov 20 12:49:00 snowball3 wireplumber[1924]: Transport Acquire() failed 
for transport /org/bluez/hci0/dev_00_1B_66_81_8D_76/sep1/fd3 (Did not 
receive a reply. Possible causes include: the remote application did not 
send a reply, the message bus security policy blocked the reply, the 
reply timeout expired, or the network connection was broken.)

Nov 20 12:49:00 snowball3 wireplumber[1924]: 0x561f089d5bf8: can't send 
command 2: Eingabe-/Ausgabefehler

Nov 20 12:49:00 snowball3 wireplumber[1924]: 
(bluez_output.00_1B_66_81_8D_76.a2dp-sink-18) suspended -> error (Start 
error: Eingabe-/Ausgabefehler)

Nov 20 12:49:00 snowball3 wireplumber[1924]: unknown AT+IPHONEACCEV 
key:2 value:0

Nov 20 12:49:00 snowball3 wireplumber[1924]: Transport Acquire() failed 
for transport /org/bluez/hci0/dev_00_1B_66_81_8D_76/sep1/fd3 (Operation 
Not Authorized)

Nov 20 12:49:00 snowball3 wireplumber[1924]: 0x561f089d5bf8: can't send 
command 2: Eingabe-/Ausgabefehler

Nov 20 12:49:00 snowball3 wireplumber[1924]: Transport Acquire() failed 
for transport /org/bluez/hci0/dev_00_1B_66_81_8D_76/sep1/fd3 (Operation 
Not Authorized)

Nov 20 12:49:00 snowball3 wireplumber[1924]: 0x561f089d5bf8: can't send 
command 2: Eingabe-/Ausgabefehler

Nov 20 12:49:23 snowball3 kernel: Bluetooth: hci0: Ignoring error of 
Inquiry Cancel command

Nov 20 12:49:24 snowball3 bluetoothd[10741]: 
/org/bluez/hci0/dev_00_1B_66_81_8D_76/sep1/fd4: fd(42) ready

Nov 20 12:49:24 snowball3 wireplumber[1924]: set volume 94 failed for 
transport /org/bluez/hci0/dev_00_1B_66_81_8D_76/sep1/fd4 (No such 
property 'Volume')

Nov 20 12:49:24 snowball3 kernel: input: MOMENTUM M2 AEBT (AVRCP) as 
/devices/virtual/input/input20

Nov 20 12:49:29 snowball3 wireplumber[1924]: unknown AT+IPHONEACCEV 
key:2 value:0

Nov 20 12:56:34 snowball3 wireplumber[1924]: 
<WpDefaultProfile:0x561f0874c260> failed to get current profile on 
device: pipewire proxy destroyed before finishing

Nov 20 12:56:34 snowball3 bluetoothd[10741]: 
src/profile.c:ext_io_disconnected() Unable to get io data for Hands-Free 
Voice gateway: getpeername: Transport endpoint is not connected (107)



I am not sure whether this is a bluetooth, pipewire, wireplumber or 
firefox issue. It happens when I try to play a youtube video on firefox 
via the headphones.

Best regards,
Julian