Can't ping remote radio every 20 minutes

RB532, Mk 2.9.8, extra channels, SR5 cards.

The link (in the office right now) seems to work fine but an over night test (running MK bandwidth tester from the remote pc) confirmed my suspicions that about every 20 minutes or so I can no longer ping the far end (monitored with multi ping to each device) The link seems to stay up but I loose site of the router. Several times on short tests I loose the remote pc. The rf link still appears to be functioning. It seem almost that one of the bridges stop working, bridging is set to dynamic, Using WDS, AP bridge, station WDS. My first kick at the cat has the same basic set up on 2.9.4 and is in production with out any issues to date. I would consider down grading the version but I need the narrow 10mhz channels for this and many future projects. As this is only my second link I am still learning the ins and outs of MK, so any help is always appreciated.

More info:

Looking at the trafic on the interface page of winbox I see no recieve trafic being recieved. When I loose site of the remote PC.