Hello everyone. I have a following problem:
I'm trying to troubleshoot a system with 2x M&S xdm46cc + an expansion base. The problem is that nothing works. Power gets sent to the keypads,they power up and respond to the button presses and remote control, but the red volume lights keep blinking and there is obviously no sound going into the speakers.It happens to all 9 zones throughout the house. I have disconnected the whole system to downsize the trouble possibilities, even removed a keypad from the wall and connected it with a jumper to the main unit. No fix, talked to tech support, not much help there, but they suggested a problem with amps/controllers. The only thing that makes me question this, is the fact that both amps behave identically. I have tried resetting the units, checked all possibilities I could think of. I want to make sure that this is a problem with the amp and not something else, before I have the customer whip out over $200 to ship them out to be fixed. Anyone with an advanced knowledge of M&S XDM46CC or XDM4600 please help.


Lots of views, no answers... guess I'll just have my customer send both amplifiers in. I thought someone will give me some reassurance, but oh well...
Thanks for viewing this thread anyways.


Same problem

Hello-- did you ever get a resolution to your blinking red volume lights / no music issue? I'm having exactly the same problem. :confused:


N o, unfortunately. I had my customer ship the unit to the manufacturer for the repairs. I'll keep you posted.


Fixed it

I called the manufacturer and they said red blinking lights simply means the keypad isn't communicating with the controller usually because the wires are improperly connected. I rechecked my installation and sure enough, doh!! I'd forgotten that patch-bay's reverse the wiring... they go from "T568A" to "T568B" at the bay. So I fixed it by reversing the wires coming from the keypads into the patch like this:

1 -> Orange/White
2 -> Orange
3 -> Green/White
6 -> Green

So coming OUT of the patch bay and INTO the controller the signals are where the controller needs them to be which is:

1 -> Green/White
2 -> Green
3 -> Orange/White
6 -> Orange

You can check first by directly wiring a keypad to the controller and it should work. Then try a cat5 or 6 "cross-over cable" into a "normally" wired bay. Assuming that also works, your system is fine. You just need to flip the wires as I've described. :)

Retired in CO

Also Same Problem

My m&s XDM46CC has been in service for almost four years (so no wiring problems). Today, when I returned from Christmas vacation, I had the same symptoms...no sound from any source on any of the remote amplifier/speakers and they all have blinking red lights on the volume indicators. I cycled the power on the central unit and also on the remotes, but the problem persists. My system is on a UPS and I completely powered it down over the vacation, so I don't think I got hit by an electrical transient. Very strange. I also am eager to hear if any other user has solved the problem other than by rewiring the units.


Same problem

Again, the red blinking lights means the keypads are getting power but not communicating for any one of many possible reasons. If you haven't changed any wires or accidentally pulled any out or cut any that leads me to think your central unit has gone kaput. You could take a keypad out of the wall (not too hard actually) and wire it directly to the central controller to troubleshoot, but that's prob unnecessary since you say you know your wires are untouched and worked before. I assume you get the same non-working system when you bypass the UPS, right? And you don't have an expansion module... or have disconnected it if you have to see what happens?

Retired in CO

Retired in CO

Same result with UPS or direct connection. Will try a single remote unit this weekend--holiday activities today. I called Linear Corp, LLC (current owner of m&S Systems) and got recording that they provide customer support only for dealers and installers. Since I bought my unit on internet in 2005, I called a Denver dealer. Got promise to call on my behalf, but am not holding my breath--rep was not familiar with product and didn't seem very interested.


Info from Linear

I got the same thing when I called a few months ago so I lied and told 'em I was an installer (actually, I am in this case... I installed it!) Here's what they sent me... it helped me enormously... hopefully there'll be a gem of wisdom in here for you too


Hi Jess,


Blinking volume lights indicate no communication. Follow normal routine of checking all the wiring. The XDM is susceptible to ESD and will fail if connections are wiggled/connected while the unit is on. So, the first course of action is to have the installer turn the unit off BEFORE checking wiring at all. If all the wiring checks out, the first suggested remedy is to swap the controller, even if the problem is in the expansion zone alone. During our testing, the controller swap did remedy bad expansion room stations. Finally, if the problem is in the expansion zone and continues after the controller is swapped, then replace the expansion hub.

If the problem is the controller locks up, but then appears to work after several days (2+) of being off, and then works again for a period of time before locking up, then replace the controller.

XDM Troubleshooting
Here is a list of potential technical support issues for
the XDM4600 beta systems in the field.
Problem: Four of the keypads don't work or have their red
LEDs blinking.
Issue: Check to see if the four keypads are all connected
to the Expansion Hub. The beta units in the field require
the Expansion Hub to be turned on before the Central
Controller. If the order is reversed the Central
Controller won't recognize that the Expansion Hub is
present, and won't communicate to it. This will be fixed
with the production units.
Problem: A keypad has its red LEDs blinking.
Issue: A keypad blinks its red LEDs to indicate that it is
not communicating with the Central Controller or Expansion
Hub. The problem is most always with the CAT-5 cabling or
the connector isn't plugged in properly.
Problem: The blue LED on the front of the Central
Controller or Expansion Hub blinks on an off. A clicking
noise inside the Central Controller or Expansion Hub is
Issue: This indicates that the power output to the keypads
is shorted. Check the power wiring. The power supply is
designed to handle a continuous short, so it won't be
damaged. If the short is a result of the power cables being
wired into the keypad's speaker output, then permanent
damage to the keypad has probably occurred.
Problem: A keypad locks up and won't accept any button
press including Vol +/-.
Issue: The beta systems have a software flaw that causes
the keypad plugged into either Port 7 or Port 8 of the
Expansion Hub to lock up after a while (several hours to
several days). Doing any of the following actions will fix
the problem for a while: do a Talk, Listen, Door Talk or
Party Mode from any other keypad, or ring the doorbell.
This will be fixed with the production units.
Problem: When two people are talking to each other one or
both keypads lock up.
Issue: When a keypad has its talk button pressed just as
another keypad is having its talk button released, one
keypad sometimes will lock up. Often this problem is fixed
when the other keypad does a talk again. This will be
fixed with the production units.
Problem: The keypads lock up or are extremely slow to
respond to button presses (5 to 30 seconds).
Issue: This problem occurs when the cable that goes between
the Central Controller and the Expansion Hub has come
partially loose. Check that this cable is plugged in
properly, even screwed down.
Problem: At full volume a keypad's audio will cut out for a
second or two. At this time the keypad is unresponsive to
any button presses.
Issue: When the keypad's audio comes back on the homeowner
only has a quick moment to press VOL- or Power to turn the
volume down before the keypad's audio cuts out again. This
is a design error, and a modification to all keypads should
have been performed to prevent this, but there is always a
chance that one keypad was missed. The keypad needs to be
All other expected problems will involve various improperly
hooked up components.

Thank You,

Applications Engineer
Linear LLC
(800) 421-1587


XDM Blinking Volume Bad Power Supply

My company (HomePlicity) installed 4 of these systems 4 years ago and each is failing at about the 4 year mark (3 so far).

The flashing volume lights are a communication error, meaning the keypads are not communicating with the controller. If all of the keypads are doing the same thing and your have checked your cables then the problem is with the controller. I would unplug the unit for a few days and see if that helps.

It appears the units work consistently and reliably for about 4 years however in my case 75% have failed at the 4 year mark.

Fortunately I have a meter and oscilloscope and determined why they are failing. The main power supply unit that feed power to the 5VDC regulator is failing.

It is not clear whether M&S replacement units have addressed this problem or not. Therefore, to fix the problem for my customers, I added and additional small power supply (fits inside the case) and injected the signal on the input side of the 5VDC regulator. My solution hopefully will not expire after 4 years.

It appears to me from my small sample size that M&S may have a flaw in their original engineering and replacing it with the same will guarantee future failure.

I hope this helps others. :)
Google HomePlicity to contact me.


XDM4600 System Issues

Like so many previous posts, I have had my share of difficulties with the XDM4600 System I installed in our home as it was being built. When it is working correctly it is a marvelous system but when it acts up it can be a real pain. Since installation June 2007 I've had to replace 2 of the XDM46K Keypads, both were under warrenty and only cost me the postage. As 'Homeplicity' posted tho, my 'major' troubles started after the system had been in use for a little over 3 years with the failure of the XDM46EH - now out of warranty of course. I purchased a new Expansion Hub and was again back in business but now the XDM46CC Control Center is beginning to show symptoms similar to when the Expansion Hub first began acting up. The system does not recover well after a power failure (fortunately very infrequent for us) or after being powered down (while on vacation or away for some days at a time). Restoral involves several power up attemps, noticing that the keypads connected to the control center are doing their 'volume light blinking' exercise while the keypads connected to the expansion hub are working fine. Eventually, usually after 3 to 6 'power down - wait a minute - power up' exercises, the control center will power up normally and we're back in business. I was surprised when I discovered that the expansion hub keypads still work fine with all music sources, even tho the control center was not communicating with it's keypads. My only other contribution to this forum is that the system does run quite warm when in any kind of enclosure. In speaking with a Linear technician awhile back, he did recommend a quiet cooling fan in installations where heat might be a problem. In the meantime, after reading Homeplicity's posts, I might just dig into my failed expansion hub and look into that power supply issue!


Update on powersupply failure.
Lately most units have beenfailingdue to bad capacitors on both the high voltage side and the low voltage side. On average I have to replace about 7 capacitors after I identify which ones have failed.I have replacement capacitor on hand. M&S used poor quality capacitors and they are beginning to fail at an alarming rate. I have been using nichicon capacitors, which are high quality cap’s. I also replace certain good caps that I find, due to the rate of failure in other units. I have learned which ones typically fail. A high pitch squeal is a typical failure of 2 caps on the high voltage side, which will eventually lead to failure on the low volt side that shows up as flashing lights.
GoogleHomeplicity to contact me.

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after limping along with these since 2006, with all the issues described above, finally going to replace. Has anyone found a system they are happy with using existing wiring, or moved to a wireless system? 5500 sq ft house so worried about fate of wireless.... thanks

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