Comment # 10 on bug 974230 from Episteme PROMENEUR

comment #9 (continued)

here
https://www.freedesktop.org/wiki/Software/PulseAudio/Notes/10.0/

i read this
**********************************************************************************
Automatically switch Bluetooth profile when using VoIP applications

Bluetooth headsets typically support both the A2DP profile, which is suitable
for music, and the HSP profile, which is suitable for telephony use cases.
module-bluetooth-policy will now automatically switch the profile of a
Bluetooth headset from A2DP to HSP/HFP when an application creates a recording
stream with property media.role=phone (telephony applications should set that
property for their streams). When the stream goes away, the profile gets
restored back to A2DP. This way the user doesn't have to manually switch the
profiles when starting and stopping a call. This behaviour can be disabled by
giving argument auto_switch=false to module-bluetooth-policy.
**********************************************************************************

this is what i want.