Just received my replacement Roku Player and WOW it also has the same fault! - It locks up/freezes when it hasn't been used for 5-10 minutes.
EG. I start watching a move via Netflix or Amazon and then click on 'pause' and then when I get back it's stuck! The only way back is to power cycle it and then wait for it to reboot. ....That's just one example, after watching a movie for 5-10 minutes it's also not possible to pause or stop or do anything via the remote control.
Do I have to send it back to Roku again or is there a fix for this problem?