I realise this is an old post now, but I repeatedly get the same problem on both the V6 boxes I have.
I get a very brief message pop up on the screen which I've never been able to read, then it just sits with the loading symbol for ages until it fails. Restarting the box seems to be the only 'fix'. It's almost like the app is always running once it's been started and just randomly crashes or hangs in the background. It's frustrating when it happens as sods law dictates it'll do it when you're recording something else and you really don't want to wait for the box to restart!