Granstream HT-386 (HandyTone) Voxalot-Voipbuster / Voipstunt Codec
 

Hello,

I have a Grandstream HT-386. My problem is with the bad voice quality.
My current configuration is:
HT-386 FXS Port1 is connecting to eu.voxalot.com.
I have a premium account in Voxalot which the service provider is Voipbuster.
Voipbuster declares the available codecs as:
G.711 (64 kbps)
G.726 (32 kbps)
G.729 (8 kbps)
G.723 (5.3 & 6.3 kbps)

HT-386 can support
G723.1, G.729A/B, PCMU, PCMA, iLBC, G.726-32 codecs.

From another post in the Voxalot Forums, it was adviced to set ulaw;alaw;g726;g729;ilbc;gsm codecs for the provider, which I did so.

Unfortunately, I couldn't manage to make it perform well and the voice is always choppy and most of the calls with an echo. Last week, after trying to use a Nokia I was amazed about the quality of the voice (where I set the built-in Internet Call).

Anybody achiving a good setup with HT-386, Voxalot and Voipbuster or Voipstunt or any Betamax services (preferably due I want to call U.S. for free).

Thanks in advance.

I have used various Grandstream ATAs and currently using HT-496 with very good voice quality (also using Betamax service). I suspect the problem may be caused by the speed or latency of your connection, or possibly dropped data packets.

A simple speed test to try is at :
Irish ISP speed test - check your broadband provider's speed

As you go to a higher bit Codec, the connection has to have a better speed rating, particularly the upload speed which is usually lower than the download speed.

Besides the bit rate "payload", there is an overhead requirement depending on the connection type (DSL, Cable, etc.)

Your geographic location may also affect the perceived delays of the voice connection, and could degrade the call experience.

For example, using a Betamax provider, and calling from North America to a European number usually has a minimal and quite acceptable delay, while calling within Nr.America to a phone down the street, may sound quite lousy due to the round trip effect to and from the Betamax servers.

For G711 codec, you do need a higher upload speed, at least greater than 90Kb/sec.
Also make sure that you do not have anything else chewing up your upload bandwidth while you are calling.
Hth ........

Hi Kurun,

Thank you for your fast response.

I have a 4Mb ADSL connection, the speed tests which I periodically repeat do give acceptable results (MySpeed VoIP connection test, VoIP test, test VoIP performance, test VoIP quality VOIP test reports radio quality). Although my ISP's QoS (Quality of Service) is not shining, I have had high quality communication with an Nokia E90 (which I told in my first post) with the same connection, which forces me for a finetuning solution research.

Hi Kurun,

I've posted a quick reply but could not see this in the thread so reposting something similar.

I have a 4 Mb bandwith connection, mostly the QoS (Quality of Service) differs to U.S. servers but good for European servers. With VOIP speedtests, I get over radio quality results. As I have treied to explain in my first post, I was trying to accept the bad quality until last week I tried internet call (built-in) option on a Nokia E90, I was surprised because it was very clear and had high quality.

Currently, I am accusing my configuration related to codec.

Thanks.

The codecs in my HT-496 are in order :
PCMA, PCMU, G729, G26-32, G723, iLBC

The Codecs on my Betamax provider list are :
aLaw, uLaw, G729, gsm

Thanks for your VoIP connection test link. It looks very comprehensive.

Hi ozerke,

I've also connected a Grandstream HT488 and IP Phone BT101/BT200 with a very good voice quality with most af Betamax label (voipcheap, voipbuster, voipbusterpro, voipstunt, ...) via voxalot server eu.voxalot.com

My voice codecs inside GT devices are very similar to yours: PCMU, PCMA, G723, G729, G726-32, iLBC.

Therefore, from the device configuration point of view the connection should be working fine.

Cheers
Paolo