Musiconhold.conf "format=" values

Hi all,
I’d like to know which “format=” values does asterisk accept when using an application at musiconhold.conf.
I’ve been looking for information but didn’t get anything clear.

Thank you!

The info has been already posted in the thread you started earlier:


yes, but there are some inaccuracies… for example, sln32 is not mentioned but asterisk 10 supports it…
so how should I write the “format=” value for sln32? I’ve tried slin32 and it doesn’t work… later I tried s32b and it does something but I’m not sure if it’s doing what it’s supposed to do…
any tip?
Thanks thor!

Please see the Expanded Signed Linear Support subsection of: … io+Formats


ok, I still don’t get what I want to know… isn’t there a list where all the format options can be checked?
in the link you shared i can see the extensions such as “.sln” and so on but, not the whole list of formats…
Sorry but I’m feeling quite stupid right now… :cry:

by the way, I got another doubt: if I write format=ulaw in the musiconhold.conf and so is the codec negotiated by the devices asterisk just passes through the data without any treatment? or decodes and codes again the stream?
Thanks a lot and sorry!