I have the Tytn2 from vodafone NL as well, and also have unfixable problems. After trying some ROM updates I figured it was a hardwareproblem and called the HTC technical service number. They will ask you about your IMEI, ROM and RADIO versions. I didn't take the gamble and told them I couldn't find it (playing noob).
The advice was to send in the device for repair with warranty (they pay)
Take a look at http://forum.xda-developers.com/showthread.php?t=335568
to restore the original state of the device.
I wouldn't take the gamble to send it in with a flashed ROM because it states in the warranty that your phone needs to be in orriginal state!!