AV1 1080p 100% cpu on S905X3

I’m wondering what I’m doing wrong, as my main Tanix X3 won’t playback AV1 coded 1080p from my plex media server. CPU all 4 cores is at 95%+.
On my other X3 box (some noname from Aliexpress) it plays totally fine with <10% CPU.
What may I have done wrong? Box is running on 21.2 Omega, only think that may be concerning is, that “Hardware” shows CPU: Amlogic unknown_soc rev c". I would expect to see 905X3 there. Right?
Any ideas what I can do? Thanks

AV1 in hardware is supported since S905X4.

So you’re saying, that AV1 is NOT supported in S905X3? My bad. Just checked, and the Aliexpress box is have is a X4. So all makes sense now. Thanks for pointing that out!

S922x actually does pretty well with AV1 using software decoding