mobile

I've been experiencing some difficulties with one of my aftvs. Last night I tried installing another game and the install hung, it took multiple reboots to kill the install, and my drive didn't remount automatically. I also noticed VERY little internal space available, despite the fact I didn't install the game and before that it had over 50% available. It was then I noticed that despite being rooted I couldnt see anything of relevance on my USB through es file explorer.
I'm just gonna wipe it all and start over but can anyone shed light/ provide tips for the new USB storage option? I was moving everything I could to external but after uninstalling several games my external is still nearly full but I can't see what's taking up space.
Sorry if this post seems a little incoherent. I figure someone might understand whatsngoing on...oh yes--Im using a powered hub. Do u think that has anything to do with the remount on reboot issue? It hadn't come up so far because I don't need to reboot this unit very often. Thanks.