| OK, well the problem hasn't come back now and it's been over a week.
The only thing I did was reset the drivers window (open full and hold switch down for 15 secs). It's probably just coincidence that the problem has gone after I did this, and I wouldn't be surprised if it resurfaces one day soon (or middle of night, knowing my luck).
One thing I will do, as soon as I get the chance, is check the BC1 for wet/damp etc.
I'll repost here if anything more happens with the problem | 
