Your problem does sound like a RCM issue.... you should check ALL the solder joints(I re-did ALL of mine to make sure they were good).... The relay contacts can be checked by separating the spring loaded plate and looking at the contacts with good lighting... if you find any that are badly pitted and black you can clean them up some with a contact file or fine sand paper... not much room so it will take a bit of work.....

The other option is to replace the RCM.... I think they go for about $150-$200....