if you did not have had such issues before, then you should investigate, what has changed.
did you update to a new version? did you change any settings? if you have another usb flash drive laying around, use it with a fresh new install to see, if the issues are present then or not.
did you ever heard of the Kepner-Tregoe problem analysis?
The Kepner and Tregoe method is used to investigate deeper-rooted problems. They defined the following stages:
defining the problem
describing the problem in terms of identity, location, time (duration) and size (impact)
establishing possible causes
testing the most probable cause
verifying the true cause