IAXY Device can call out but will not accept incoming calls

I get the error in Asterisk:

Rejected call to 192.168.1.50, format 0x4 incompatible with our compatiblity 0xff83.

It appears to be a codec problem. I had this working before using a TDM400P. It’s now going through a PRI.

I have iax.conf set to ulaw:
disallow=all
allow=ulaw

The iaxy provisioned for the same.
codec: ulaw

Any help would be appreciated.

Resolved:

Need to have “allow=all” also in general section of iax.conf

Interesting. So if both wanted ulaw, why was it failing? What is actually being negotiated?

I have seen this before when the far end will only work with a particular codec and the near end will only work with another.