Pointless asking as LG SHOULD just list models and magic remote compatible to save customers asking forums which are filled with people who don't help!
It sounds like you're having a frustrating HDMI problem after the latest software update. Other users have faced the same issue, and the only solution for now seems to be turning the devices off and on. It's not the best fix, but it might help until LG releases an update. Let's hope they sort this out soon!