We'll done a pic of a plug with a broken resistor. Only time you see it if you drop and break that plug. Think you will find it's main use is radio surpesion. Not 100% sure on that though. Do remember reading about it some time back. Like I've said earlier if you change your plugs regular they really don't give much trouble.
It's all in the detail.
Btw cream puff I use to sent aircraft in the middle of aust and never had a problem this was we on top of our planes and pilots. Might won't to have a look what's in the middle of aust and see what support is there. See it cost an awful lot to send an engineer on a break down here. It would seam if you are having trouble it may be something else wrong with you machine
Cheers