RAID rebuild taking days/weeks/months/not working?

Hi folks - I know this is an older thread but I’m having a similar problem with my My Cloud Mirror 8TB though the suggestion above for raising the speed limit didn’t seem to help. In my case it’s running around ~64K/sec (I’ve seen as low as 40K/sec and the highest about 200K/sec). I just posted this thread in the Mirror forum but thought I’d cross-post in hopes that any of you had a suggestion for a way to disable the RAID rebuild process.