Hi secreagent, I had the same with my 1st air lock - I changed it to a cup & cap air lock & havent had any problems since, on your next brew try the cup & cap.
Nick
I don't use airlocks.
I cover my fermenter with Gladwrap, and put a rubber band around it to hold it in place. The rubber band is actually the sealing ring I've extracted from the inside of the lid.
And best of all, it allows me to see exactly what's happening with my fermentation.
