Required Information
- DietPi version 9.18.1
- Distro version bookworm
- Kernel version 6.1.115-vendor-rk35xx
- Architecture arm64
- SBC model Radxa ZERO 3 (aarch64)
- Power supply used USB-C from PC
- O/S in mmc
Additional Information (if applicable)
- Software title alsamixer (1.2.8), Direwolf (1.6)
- everything installed by apt install from distro
- Can this issue be replicated on a fresh installation of DietPi? YES
I am running Direwolf + Digirig Mobile (which has CM108 chip IIRC) on DietPi 9.18.1 and all the time I am getting warning messages in Direwolf that the audio input is too high (basically it seems to be clipping for any signal except very weak). In alsamixer (v1.2.8) I switched off AGC for the recording device and despite any reduction of gain (the minimum is 2, approximately -21 dB) it seems that nothing changes at the input of Direwolf. In Direwolf’s relative units most signals come at levels 125-127 (127 is maximum I believe) and weaker signal from another station comes at level 72 regardless of settings in alsamixer. That seems to indicate that the setting has no effect at all.
When I connect the same hardware to a Windows machine to see if the problem is not in hardware, I can control the input level easily, setting it at 40% of the scale ensures optimum levels.
Q: is this a bug in alsamixer or what else could I try to reduce the input from recording device?