Thanks guys....I appreciate the feedback. Ironically the bubble has gone away....I dunno if that's good or bad? I don't think it got warm anywhere so not sure how it disappeared. I will pick up a spare but it's still working so I'll keep using it! And I compared it to my gps and its still very accurate so I'm a happy camper. Normally things like that only happen AFTER I buy the teplacement. Ha!