I don't believe that there is a riff between BB and Weis. As recently as 2011, BB was quoted re: Weis and his commentary on him was warm.
Belichick keeps strong ties with Weis - New England Patriots Blog - ESPN Boston
What is absolutely true is that philosophically-speaking, the Pats do not pay top-dollar to coordinators. They believe that the coordinator position is a stepping stone and people that occupy those positions aspire for more than just be be paid. There was some rumbling back in 2003 that Weis was disappointed in his salary but I think that was a far as it went.
BB/RAC- My understanding is that their relationship is more of a professional nature. Not aware of any riff so not comfortable to comment.