I am using the most recent (20210804) version of hifiberryos. I am having two problems that may be related.
1. I have a touchscreen attached to my raspberry pi, but the when I use the master volume on the screen, it doesn't respond. If I use the web interface, it works just fine.
2. I purchased a USB volume knob (https://www.amazon.com/gp/product/B08NJMPXTT/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) which works just find on my Linux workstation, and the OS recognizes it, but it doesn't control the volume either.
This is a bit of a family-acceptance-factor question, as many in my household would rather turn a physical knob than get out their phone to adjust the volume.