Double Tap, did you do a factory reset after the Lollipop upgrade? If not, you should give it a try. Look in Settings then Backup & Reset. Make sure that there is a backup account listed, and that the Backup my data and Automatic restore options are toggled to the on position. If you have music, photos, videos, etc stored on the N7, back it up to a PC. After you hit the command to proceed with the reset, it will eventually restart and give you the opportunity to login - use the same account that was listed as your backup account. The tablet will basically reconstitute itself. It takes a while, but it's not as intimidating as flashing.
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