If it's software related perhaps a full firmware update would help. Instructions provided below.
How to initiate a full firmware update?
In some rare occasions it might occur that the software
on the device goes corrupt even preventing one from doing
a firmware update. In such case, follow the steps below in
order to enforce a full firmware update:
Start the firmware updater.
Undock the TSU9600 and press the Next button.
On the next screen press the Troubleshoot buttton.
Place the TSU9600 into the docking and wait for the Repair
button to enable itself.
Now reset the control panel by pressing the key combination:
Page +, Home and Menu simultaneously immediately followed
by the next step.
Within 2 seconds set the firmware update flag by pressing
the following key combination for 2 seconds: Firmkey 2,
Firmkey 3 and Firmkey 4 (below the LCD) simultaneously.
The control panel will now start up showing a dialog
saying: "Application Firmware Download mode, normal
operation not possible".
Finally press te Repair button and wait for the update
And yes, my beloved Pronto Professional TSU9600 remotes and RFX9600 Serial Extenders are still the only game in town. Pronto for the win, baby! :-P