Leaking Diplomat AHY 8102/1 dishwasher?

Periodically during the cycle a small amount of water comes out from under the machine on the right hand side. It's only about 20-30mls but even that will damage the wooden floor eventually. It doesn't seem to be coming from the door seal, it's from right underneath the machine. Sometimes there is no leak. Also at the end of the cycle when I open the machine I usually find that the lower spray arm has fallen off and is just lying on the bottom of the machine. Is there any connection here? I've heard of lower spray arm problems but usually with it splitting - mine doesn't have any splits, it just falls off.

Pete
January 2013