Not a known issue, but there is nothing we can do if you don't follow the bug report guidelines. I regularly work with projects for longer than 20 minutes and haven't seen any such issue. Please provide all the required details in the bug report template.
i KNOW THIS
I GOT THIS OFTEN
I FIXED BECOZ I NOTICE THIS IS AUTO BACKUP>HDD PROBLEM
TRY SETTING YOUR BACKUP HDD DONOT SLEEP
OR JUST DISABLE AUTO BACKUP