This seems to be a prevalent problem for Fenix - and Armbian - desktops on the VIM3.
There are unanswered questions for this issue in multiple threads, going back to TWENTY-NINETEEN. LOL
I have a complete solution for Fenix and Armbian systems, cribbed shamelessly from LibreElec and Manjaro.
It is detailed with meticulous configuration guidance in UPDATE 2 on my topic:
2ND UPDATE - Success Running Twister OS Armbian on VIM3! Fan and AUDIO
I hope that this is helpful to someone else!
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