Hi Todd,
U2 is the 1.2V voltage regulator for the DSP Core. It normally runs warm but you should be able to leave your finger on it indefinitely.
LD1117DT12 800ma IC LDO REGULATOR +1.2V DPAK ST LD1117DT12TR
My guess would be something in the DSP is drawing excessive current.
Did you try re-flashing the KFLOP Firmware with the "New Version" button. Unlikely to be a software problem but possibly worth a shot.
KFLOP by itself with nothing connected should only draw around 0.3A.
R5 acts sort of like a fuse to limit current draw from the 5V. Rev 1.1 used a 1ohm resistor. In later versions it was changed to a 0.1 ohm resistor because in cases of the 5V being low (ie 4.5V) and with large currents it would drop the voltage too much. Changing it to 0.1 ohms may allow it to then operate on 5V but wouldn't explain the large current.
Rev 1.1 boards were shipped over 6 years ago. Maybe time for a new KFLOP
Regards