I'm use HTC A9 connect to Car Think+ Touch via Bluetooth and enable automatic-record, it no nound and can not record.
But disable automatic-record, all ok, no problem.
I'm test all mode that same result.
HTC Android 6.0 has a minor bug in the ROM related to bluetooth recording - during the call when a recorder start recording the ROM switches audio from the bluetooth device back to the phone earpiece at once, you need to disconnect / reconnect the bluetooth device, then bluetooth recording works.
We found this bug in following phones so far:
HTC 10 Android 6.0
HTC A9 Android 6.0
HTC M8 Android 6.0
No matter what recorder you are using the problem is always there, because the problem is inside the ROM.
Third-party apps can't fix the problem. Users have to wait HTC to fix it in future ROM updates.