You guys may be on to something because that gasket is in a bad state with part of it missing. I attempted a repair with some aviation gasket goo but not a good one. I have some gasket paper here somewhere and I'll give it a go. I didn't realise it could make the difference. I have also been thinking about an ultrasonic cleaner. I have been thinking about this one as it has a 6L container and I can do other stuff with it
Ultrasonic Cleaner Sorry vcomm I posted at the same time as you did and so missed your answer.
