CallerID from analogue FXO (Digium) not passing to SIP destination


I currently have my FreePBX system setup to have all inbound calls route to an IVR, which then routes to appropriate SIP phones depending on choices.

Now, if I look in the Asterisk console, when an incoming call comes in, I can see the number, however at the SIP phone, the CID is just ‘Unknown’.

In both chan_dahdi.conf and dahdi-channels.conf I have set usecallerid=yes and callerid=asreceived.

I’m stuck now, I’ve spent hours googling the issue to no avail.

Edit: oddly, when calling in to the GSM interface on the box, rather than going through the IVR it just dials an extension (I haven’t configured it to do this, I just have one inbound route as no one will ever dial in on the GSM interface), where callerid is passed to the phone just fine.