"Interesting news on the Zune front: a friendly tipster's buddy works at a Microsoft call center and handles Zune-related issues. Apparently they've received numerous reports of the Zune screen cracking for no apparent reason, after being left charging overnight. Our tipster's friend conjectures that the lithium ion battery -- which resides right behind the top half of the Zune's screen -- is expanding from overheating and putting too much pressure on the screen, causing it to crack. Unfortunately, Microsoft currently regards the issue as outside warranty coverage, leaving the victims with a broken Zune and nowhere to turn.A quick skim of the Engadget comments sees many Zune users leaving their devices charging overnight with no problems whatsoever, so it's tempting to tag this whole story as "nasty rumour slash scam". Although, if you're one of the few who have reported cracking screens to Microsoft, we'd sure like to hear from you.