If anyone is having trouble with the Seek function being quite sluggish on the ONN 4K Pro box, I was messing around with my Channels settings last night and found a combo that sped up Seek/FF/RW drastically for me!
- Playback>Home Streaming>Set to "Stream"
- Playback>Advanced>Video Decoder>Set to "Software"
Could be just a combination of my gear, but this worked wonders for me! Compared to my Shield, FF/RW & Seek on the ONN box were barely usable before I made these changes, now it is much, much faster. Almost on par with the speed of my Shield.