Rear lights Weirdness?

Anyone had any issue ps with the brake lights comming on? Mine seen to have a life of their own, just work wjen they please! Were not working today, check fuses and power to bulb connections, all working just fine, power supplied when it should be etc. but put the bulb in and....no brake light! Messed around, bulb in, bulb out, no joy, then hey presto it worked! No idea why it stopped or why it started again! Anyone else had same issues? Its definately the bulh holder I think as meter showed 12v every time when I tested it wether it was the lights fillament connector or the stop bulb fillament connector.

I would check the switch has not gone faulty
it is live all the time,if there is 12v at the bulb holder intermittenly to me that points to the switch

whoops just read your post properly u have checked that already sorry

Checking voltage With bulb in, is there volts showing on bulb + connection are there battery volts ? if yes if check earth side of bulb for volts if volts here either poor earth or faulty connection in holder assembly.
If answer to first question is no or low look at switch short it out to test , if still low or no, look for broken\corroded wire, connector\plug
You have checked bulb of course, have had bulbs high resistance intermittently over the years (50 in motor trade)

Yes checked switch first then shorted so I could test at back. Will check bulbs again when they next stop working.

Well, they played up again today after working last night so bought two new bulbs and they worked first time I plugged them in and still doing so when I checked after getting home tonight. Just wondering if the contacts on the base of the bulb have vibrated and worn uneven (they looked a bit scratched and scuffed) i.e one higher than the other and as the contacts in the light are flat on a spring loaded plate, one contact wasnt touching when the other was? Can only see this as reason when new bulbs work. Old bulbs were not blown a I used a metr to test them.

Flick the bulbs, sometimes the filaments have a little break but they sort of weld themselves back together.

The existing ones have been consigned to the spares bin marked S for scrap! For the cost just got new bulbs and I hope sorted it, thanks.