I have found that once the device changes to UNKNOWN, if I do a reboot and hit F8 and choose "Last Known Good" everything goes back to working order. I still haven't been able to find the permenant combination.
A warning to anyone that plans to post "Send it back" this is not a solution. After doing many searches. This problem can effect any of the touchscreens used by our members. The only common trait are the drivers.