Mirrorview A Functioning only one SP ?

I  configured Mirrorview  between a CX4-120 and CX700, fibre attached.   Only LUN's owned by SPB  are being replicated.   Any mirrorsets owned by              SP-A fail to synchronize. 

In Mirrorview Connections it shows both SP's are connected, but if disable and reenable the connection I can see   SP-A  not connecting sometimes, as if the port was flapping.

I ran tests from my switch, end to end,  with no problems.  I am using dedicated ports for mirrorview, that are in a separate VSAN from the ports.  The zones

are configured as

CX4  SPA -1 <->  CX700 SPA-3

CX4  SPB- 1 <->  CX700 SPB-3

Has anyone else seen this?   I can't think of any other tests to isolate the problem.