I don't know whether there is a solution for this or that it is ANOTHER FEATURE of the car

I like to listen to Talk Sport on medium wave but I get a lot of interference marked with the use of acelerator and in old days we used to put a capacitor inline to cure it but do we still need or are able to do this?

What is strange is that I can clear a lot of the interference by pressing the screen wash button or sometimes just switching the radio off and on again, also and i don't know why but pressing the clutch in and out will effect the radio like there has been a lightning flash (a crack sound) why would that be? is the clutch electronic?

Final question could this be a sign of electrical fault, earthing or anything?

The main problem is that medium wave is rubbish! :P

Seriously, MW is very prone to interference compared to FM. Any slight anomoly either inside or outside your car has the potential to affect your signal. If this has started to get worse or is constant then it is likely that your aerial is at fault. It could be anywhere between the plug on the back of the HU, the wiring or the antenna itself. Any slight degredation of these could cause MW problems. You may not notice on FM because the signal is much stronger and works differently.

Only way to diagnose is to try and eliminate piece by piece. Remove the HU and check the aerial connector is a good, snug fit. Look for damage on the wires that you can see. Unscrew your antenna on the roof and reattach to ensure a tight fit and, again, check for any damage.

After that, you are into the realms trying another aerial with your HU or your HU with another aerial, checking wiring that you cannot see, etc.

It could also be a HU unit problem but my money would be on the aerial.

Cheers

Rog

I'm sure you can still buy inline aerial filters from Halfords or Maplin that should screen electrical interference.

Phones and in my case police radios affect the signal too and is annoying but our work cars have filters all over the job due to all the extra electrical kit that is fitted to them.