Whole Home DVR & Network - DirecTV DVR

For Whole Home DVR & Network, relating to DirecTV DVRs and receivers. Have had service guy out several times from DirecTV installer. The Whole House DVR works fine.
Currently have a H24-100 and 2 HR24-500 (HD Receiver and 2 HD DVR's). The receiver sees both DVR's and the DVR's see each other.

The installer put in a DECA with power and connected to a port on the router, then plugged the other end to the SWM LNB next to the dish using a coax.
When the network is plugged in, one of the DVR's kinda goes away. It won't download a VOD properly. It won't see the other DVR.
The other DVR nor the receiver won't see that DVR either. The one DVR that the receiver can see, can download VOD content.

It doesn't matter if you reset all DVR's and receivers.

If you unplug the DECA from the network and from the SWM, the DVR's will see each other again and the receiver will see both.

Any ideas?