Ok, I bought an OTG C to C adapter for my phone (phone is Samsung S20FE at latest software) but the DAC function is not working. Adapter is this one
https://www.amazon.co.uk/gp/product/B07THMD9D6/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
With this adapter, my phone can see and explore USB storage drives (so it works and my phone supports OTG) but it will not work with my Fiio M9. When I first plug in, the screen momentarily flashes up on the M9 to say ‘DAC’ and reports 48Khz 24 bit and maybe this is the problem….. the files I have ripped onto my phone are flac (44.1 and 16 bit, same as the cd) or I’m using Spotify so it seems like, in DAC mode, the M9 is maybe choosing the wrong sample rate and won’t sync?? I have rebooted both devices and tried reconnecting multiple times. My M9 is at the latest 1.07 software, I am selecting USB DAC in the pull down menu in the M9 and the USB cable I am using to connect the M9 to the OTG is one that works just fine for connecting the phone to my car for Android Auto so it’s good enough to pass audio just fine.
Is there anything else I need to do at either end to make this work?