IGNITION: Key Removal Sensor - Switch or Barrel?

[Howzat]

So you switch the ignition off and the radio stays on if you dont remove the key but mine has developed a fault where sometimes the radio goes off like there is a loss of contact.
It's getting worse quite quickly and I suspect it wont be long before I lose this feature altogether.
Is this gonna be the ignition barrel or the switch behind the barrel? Anyone had similar and fixed it?

 

[mmi]

Does also "Terminal S" fade away - while key still in the lock?

• in BCM block/channel 1 - value 1.

 

[Howzat]

I'll see if I can find that using OBD11. It's just like I've removed the key but if I wiggle it a bit the radio and other electrics come back on.

 

[Lightrofit]

There's a microswitch at the very back of the barrel that the key pushes when inserted

 

[Howzat]

Thanks. Time to try some contact cleaner then. I that doesn't work what would be the solution? A new barrel or is it the switch that sits behind the barrel as shown below?