Codec selection PCMA & PCMU

[Randika]

Hi

Although all our extension is configured PCMA as the preferred and PCMU as the second preferred, 3cx always forcing PCMU for the recipient side and PCMA for the caller side. I am referring to an internal call between two extension.

Is this codec translation have any impact on voice quality ?

Is there any way we can change this for both phones to use the 1st preferred codec (PCMA)

Thanks

 

[lneblett]

There is the phone codec setting and the one that 3CX uses for the providers and perhaps the phones if the PBX is set to deliver audio. Reinvites could also be a factor to look into.

You need to ensure that all are set to the desired codec with the desired preference. Many phones have the capability to remove a codec from the line-up thereby forcing the issue (although this may require a template modification or manual provision). Also, in the US, the desired codec is 711u whereas in Europe and others 711a. Depending on the provider, they may have a limitation as to which codec they support which also might be a factor to consider.