stuttering

My Xiaomi Mi 10 Ultra is running on the latest MIUI 12.5 stable ROM and i am having problems with video stuttering. I am writing in this section, but i am not sure if this is a bug related with the ROM, because this problem is here for a couple of days. I had really gut videos with this...

Since the latest weekly, I version 7.9.14, my phone stutters and lags. Mostly this occurs when the on screen keyboard comes up and I try to type something. This was not present in the version 7.9.7. If I start typing a word, nothing happens for a while and suddenly the entire word appears. Also...