Thanks for the quick reply! It reminds me that I had the same problem on my PC a few years ago, now everything is working fine!
I am currently trying to package gstreamer and add support for the RKMPP plugin, and I've seen some of your attempts on the new kernel regarding hardware codecs, but I'm not sure if it's a good idea to switch to the latest kernel: will both the VPU and GPU work as well as the legacy kernel? Thank you!