Distorted recording with certain mic (but not in pulseaudio) about bluez-alsa

[borine]

Please can you state:

• the version of bluealsa that you are using, and if self-built from source the options used for configure.
• The codec and sample rate used by both the devices when used with bluealsa and when used with pulseaudio
• the application used for recording with bluealsa (with settings used for sample format, sample rate and channels)

I don't have any echo-cancelling devices to try this for myself, but if I am given enough information to reproduce the rest of your set-up I may be able to track down some possible causes.

[lowlyocean]

Sure, not built from source - pasting relevant distro-provided packages:

> ii  bluez                                            5.66-1+rpt1+deb12u1                       arm64        Bluetooth tools and daemons
> ii  bluez-alsa-utils                                 4.0.0-2                                   arm64        Bluetooth Audio ALSA Backend (utils)
> ii  bluez-firmware                                   1.2-9+rpt3                                all          Firmware for Bluetooth devices
> ii  bluez-hcidump                                    5.66-1+rpt1+deb12u1                       arm64        Analyses Bluetooth HCI packets
> ii  libasound2-plugin-bluez:arm64                    4.0.0-2                                   arm64        Bluetooth Audio ALSA Backend (plugins)

Sample rate & format for speakerphone with bluealsa: arecord -vvv -f S16_LE -r 8000 -c1 <file.wav>. Logs indicated codec was CVSD

For pulseaudio I run systemctl mask bluealsa.service followed by rm /etc/asound.conf, and reboot; then after bluetoothctl connect <address> and pactl set-card-profile bluez_card.<address> handsfree_head_unit, I run the same arecord command

[borine]

arecord -vvv ...

The output from that should show the setup of each ALSA plugin used. Please could you post that section of the output so that we can see which plugins are used, and what the setup of each is? It is possible that the pitch-shift may be caused by a plugin; but it is also possible that dropped SCO frames may result in a raised pitch, combined with frequent underruns. (In this case playing from the hcidump file would also result in the raised pitch, but without the underruns).