I bought my focus 2001 around October 2014 and the previous owner had made an absolute mess with the wires to the stereo cutting the harness off and using gaffer tape to, well make a hash of it. I have put this right using a soldering iron and shrink rap.

My problem is the stereo will play perfect until, I lift my foot off the clutch and then it cuts out I have tried many things to sort this but I still have the problem.

I have, checked and double checked all wires, changed stereos and battery, reground, and taken out the clutch switch.

I have no other electrical problems.

Sounds like you've got a bad connection near the clutch pedal.

I think it could be pure coincidence that your radio cuts out when you take your foot of the clutch,,,,I say this because obviously you are disconnecting every thing when you push the clutch in,,,,and when you let it up you are just taking the pressure of,,,,unless the flexible line to the bell housing is moving when you let off the pressure and possibly disturbing some thing around the battery box,,,like I say I think it is coincidence though.

The only electrical switches you have to do with the clutch is pedal switch, goes to earth and to fuse box, clutch fluid level switch? Not all MK1 have them, and the fuse.

Have you tried the radio with the engine f if you can use your radio that way which I believe you can and then just operate the clutch pedal see what happens,,I don't think it would have any thing to do with the pedal switch,,,,if it was loose you would here it when you let the clutch up.

Do you know anyone who has a car like yours that you can temp swap the radio units over see if it still does it,,,keep us posted as to how you get on tho!!!!!!

Paul