Connecting my HR54 to the internet (wired or wireless) crashes my entire home network.

I recently built a new home and had Directv installed.  We have a full home automation system.  For months, every time we try to connect the Directv boxes to the internet, wired or wireless, it crashes EVERYTHING on the network.  I have to do a full reset on everything and disconnect internet to fix it.  I've had two techs come out in the last two weeks and tried everything from adding a DECA bridge to new boxes completely.  Nothing is fixing it.  They both gave up and left.  Any suggestions for anything on my router I need to change or set?  We have gigablast internet, so it definitely is enough to support it. TIA!