Audi A3 2010 1.6 Loosing Power In 2nd Gear

Audi A3 2010, 1.6 BSE, LVN manual transmission.

The car loses power when driven in second gear.
Drives fine in all other gears and there are no fault codes.
The board computer/DIS shows the gear selected for all other gears except second.
If I dip the clutch pedal without making it slip the power returns but the gear display remains incorrect.
There is no neutral switch (no stop/start) and there are no other transmission switches to provide the info.
I presume the gear selected is calculated from the road speed and the engine speed. (Probably an ABS TC function).
The gearbox had previously been repaired and I suspected the wrong ratio second gear had been fitted... removed, stripped and counted teeth=correct ratio.
All the Googling I have done shows its a fairly common fault but only points to unplugging the clutch pedal position sender to keep the power.
I would prefer to correct the actual fault rather than hide the symptoms.
If anyone has any ideas or a link to an SSP for the board computer on the Audi's it would at least give me somewhere else to look.

Thanks for taking the time to read my novel!