HPEC Clipping low volumes


Recently I bought 4 HPEC channels.

I implemented them with very disappointing results.

Asterisk 1.2.15 / Zaptel
Using 3 x x-lite and 1 x Aastra 9133i
Pentium 4 3.0Ghz / 1Gb Memory.

The HPEC install was successful. The echo was COMPLETELY ELIMINATED in the beginning I was amazed with the effectiveness of the HPEC.

The problem was, the audio was almost completely one way - unless the remote caller / called party shouted. All normal/low volume audio was clipped. The only sound that could be heard from the remote caller / called party was if they shouted - and then it would just be the peak of the sound. Audio from the Asterisk end out to the remote party was working as normal.

I tried many different settings including various levels of RX/TX gain. I variations of settings of echocancel=, echotraining= and echocancelwhenbridged= in zapata.conf. I found HPEC worked when all of the above where commented out.

I was on site from 09.00 until 15.00 and in the end, I had to revert to running WITHOUT hpec, and promise the customer I will come back with a definitive solution on Monday. I have reseigned myself to footing the bill for an Analogue card with hardware echo cancellation. (Sangoma A200E) - It was either that or remove the Asterisk installation completely.

I am disappointed with HPEC, and at spending $40.00, and also that I have to spend £270.00 for a new card / modules.

Does anyone have any idea how I can stop HPEC clipping the audio? I tried Digium support by email but have not had a reply yet (approx 30hrs).

I would try Octastic Echo Cancellation software, but the client is getting a bit fed up of the sight of me. I need to get this sorted and the only possibility I can think of is the A200E.

Any assistance greatfully received.


No replies?

Does this mean few are using HPEC or few are having problems with it?

Advice appreciated.

i did some testing with the HPEC on a smaller system; it had some issues and i did work with digium support on the matter, however after some thought i pulled it and also decided to try the analog fxo offering from sangoma that includes hardware echo cancellation

im still waiting on the new hardware to arrive but the results others have reported on the net look promising

I am also experiencing the same problem. HPEC cutting sounds on low volume and I have to put my mouth very close to my cell phone speaker in order to hear my voice on another IP phone I was using during my testing.

I had to pull the HPEC out and use MARK_3 echo cancellation module configured in zaptel/zconfig.h instead.

It works better but I still having one problem where I could hear my voice at the beginning of the conversation before it faded out later on.

This problem has been corrected. An update will be available shortly.

This problem certainly has been corrected.

I installed a Sangoma A200E today and VOILA! Echo gone.

Next time I do an install, I will carry both TDM400 and A200E with me and if any echo’s occur, I will be able to solve them on the spot.

However, I still look forward to getting a reply from Digium support to my ‘HPEC Clipping low audio’ support request sent in last Friday.

Digium support is currently back logged on cases.

Make sure to have echocancelwhenbridged=no and also a valid echocancel value. These have been known to cause issues with the latest HPEC. Digium support can provide an older version of HPEC which doesn’t have this issue. A new HPEC version should also be available in a few days.

Of course it got rid of the echo with the Sangoma card, it has an echo can module on the card where as the TDM400P does not.

New version of HPEC is out.