Here's my setup:
-- 3 HD-DVR receivers in different rooms, all using SWM and whole home viewing.
-- The room with the cable modem has an HR24-500. The other two have HR22's
-- The 2 HR22 rooms have DECA adapters. The sat coax from the wall goes to the DECA, then further coax from the DECA to the DirecTV receivers. An ethernet cable goes from the DECA's to switches, with outputs to the DTV receivers as well as the TV's and blu-ray players or Roku/Apple TV's depending on the room. This has worked flawlessly since install in the very early days of DECA installs. No room has more than a few other devices on the switch and most are dormant (i.e. off) at any one time.
-- The HR24 takes advantage of the fact that I originally had two wires before SWM. One coax goes from the wall straight to the HR24 which has SWM and DECA built-in. The second goes to a DECA adapter that connects by coax to a switch (same as other rooms, but one of the ethernet's from the switch goes to the main WAP/ROUTER that connects to the cable modem.
-- All cabling is Cat 6, all switches are unmanaged gigabit, the WAP/Router is an Apple Time Capsule with gigabit capacity.
It's worked beautifully until a few days ago. Absolutely no equipment changes, etc. preceded the change.
Here's what's happening now. The HR24 in the same room with the DECA that connects by hardwire eventually to the cable modem still connects to the Internet but in the diagnostic gives an error that the router signal is compromised. It lists the serial Number for the DECA adapter in that room. All internet connectivity to the HR22's and all other devices in the other rooms is completely dead.
Here's what I have done in terms of ruling out other things besides the DECA adapter in the main room:
-- Reset every box and DECA between each step.
-- Took all the switches out of the equation so only the DirecTV boxes and DECA adapters were connected.
-- Hard-wired the main DECA adapter directly to the cable modem, by-passing the WAP/Router
-- Swapped ethernet cables with cables I know to work and tested with other devices
-- Plugged by laptop into the cable modem using the same cable I direct-tested to the main DECA just before and after it and got consistent, stable results above 50mbps
No change in behavior.
It seems to me that my problem is a failing DECA adapter in the main room that hardwires (through a switch and router path) to the cable modem. It's a bit odd that while it kills connectivity from the remote rooms it only compromises it in the local room. But it seems like that DECA, which is in the critical path of connectivity from the remote rooms, is the common link to the problems and is called out in the local boxes diagnostics. The only two thing I have not tried yet is taking the DECA out of line on the local box and using the ethernet port to try and get connectivity, or swapping the DECA in that main room with one of the secondary rooms and seeing if it at least solves the problem for the main room and one of the two remote rooms.
Does this sound like the right diagnosis? If so it seems like a replacement DECA adapter should fix it.