A test video name on Youtube with the problem?
Please do some read/write speed tests
https://play.google.com/store/apps/d....a1dev.sdbench
https://play.google.com/store/apps/d...isk.speed.test
For a solution you can try this
In folder mount app after rooting, mount the Youtube folder to a fast USB flash drive or Micro-SD card.
The folder will be something like this - /storage/emulated/0/Android/data/com.google.android.youtube/cache/exo
Just copy the correct folder name path by searching for the folder in MiXplorer.
https://play.google.com/store/apps/d...evasque.fmount
I will test different Youtube apps 32-bit also since the included one is 64-bit and some other optimizations that might help to solve the problem a different way.
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