Originating a call between asterisk servers results in error

I’m trying to originate a call from one asterisk server to another (I’m using ARI to originate the call, but it’s going through an outbound trunk).

I’m receiving an error though - 488 not acceptable here.

I’m pretty sure this is something to do with the codec…perhaps because there’s no actual phone either end? But it feels like it should be possible.

Thanks for any help!

Please provide the configuration information as well as the SIP traffic. A 488 does indeed usually indicate a codec configuration issue.