Which home screen - website, browser....?
When does that return happen: e.g., "right-click", random, maybe after some audio activity...
What browser are you using?
Have you downloaded any new games (trial versions or othewise)? Could be there was some limitation within the code for that game and that "code" is being applied to all games/websites.
Did you or do you use any programmable keys - maybe some misconfiguration is causing some action on your part to be the "return".
Try to narrow down the circumstances. Disable or otherwise prevent background apps from launching at startup. Then play as normal.,
Start enabling the apps one at a time and see if return problem can be associated with one particular application.