Hard ware echo cancellation problems

Card: AEX410 with echo cancellation module: VPMADT032
I have searched everywhere and can’t get my hardware echo canceller to work.



This was my last attempt. I’ve tried commenting out the echocanceller stuff, changing them to mg2 and others, I can get the software echo canceller to work alright (not great), but I bought echo cancellation cards to solve the problem, and i cant get them to work.

When i remove ALL swec, i get the echo bad.

dahdi_cfg -vv says:

DAHDI Tools Version - 2.6.1

DAHDI Version: 2.6.1
Echo Canceller(s): HWEC

Channel map:

Channel 01: FXS Kewlstart (Default) (Echo Canceler: HWEC) (Slaves: 01)
Channel 02: FXS Kewlstart (Default) (Echo Canceler: HWEC) (Slaves: 02)
Channel 03: FXS Kewlstart (Default) (Echo Canceler: HWEC) (Slaves: 03)
Channel 04: FXS Kewlstart (Default) (Echo Canceler: HWEC) (Slaves: 04)

4 channels to configure.

Setting echocan for channel 1 to HWEC
DAHDI_ATTACH_ECHOCAN failed on channel 1: Invalid argument (22)

The best swec result I’ve gotten were using mg2 and fxotune, but there was still an audible crackle every now and then when I stopped speaking.


  • I’ve tried variations of this, I have the echocancellation stuff commented out right now because I was trying to totally OMIT anything that could activate swec.

Please help someone. This is stressing us out!

Did you follow the Digium rules for installing the proprietary software specific to your hardware?. If not start here


Ok, so you have to purchase a license for the echo cancellation card…gotcha. I just bought the license and am waiting for something…I got a confirmation email. Is there any light you can shed or pointers that would be handy about the installation and configuration of the license / software that would keep me from asking more questions? :wink:

Not really, just read your email and do what Digium suggest.

If you bought a legitimate Digium Product, then you should not have to pay for it, it is included in the price, at least at was the last time I bought one.

I bought a knock-off from China with Digium stickers. I don’t know if they’re stolen or what. E-Bay didn’t mention, but I’ll give it a go. Thank you so much for your help!

Then curiously Digium expect you to pay for your (in my opinion) unethical purchase to work with their hard earned efforts :wink: no? But also be aware that the license you bought might well not work on the illegitimate hardware you bought.

Do me a favor, take of all your clothes and only put back on what label says it was made in the country of your choice, when you stand there naked, don’t be surprised.

(bought to you by Bain Capital)

True. I bought the license. I DO plan on getting with Digium and trying to become a reseller; we’re building business server systems that will have telephony functionality among other things. I WOULD like their support. I bought the card off of E-Bay cuz it was cheap and quick. I actually didn’t expect it to work at all. I was surprised. But dont worry. I’m patriotic enough to purchase all production items legitimately…Your helpful advice won’t go to finance the commies…scouts honor.

I appreciate your ethics.

See this thread www.freepbx.org/forum/freepbx-distro/distro-discussion-help/tdm800p-echo-cancellation-not-detected, I think it may help.

To use the card without the module you need to physically remove the module and then do fxo tune.