Troubleshoot Remote App Hanging

[itworker247]

I have an AVD deployed w/ one session host for 6 users using one published remote app (Quickbooks).  We don't present the full desktop.

Occasionally one of the users will experience the remote app hanging or appearing to be frozen.  The only way I can resolve is by forcing a logoff of the affected user.  Once logged off, they can log back in to remote app and continue working.

I'm hoping someone can point me to a resource to troubleshoot this.  I've reviewed event and system logs and don't see any clues there.  

Thanks for any help.

[#2]

The behavior is like if another window or notification popped up behind the app and taking focus away from the main app. The user can't see this so they can't click to clear and return focus to main app. I'm trying to find a way to confirm if this is what's happening or any other kind of info that could explain what is happening in that moment. I temporarily gave this user access to the full desktop (while remote app appeared hung). When I logged into full desktop, I was hoping to see the same quick books session with any other things that might be running, but it was a different instance with nothing running at the time but the desktop.
I hope this makes sense