Sorry, I accidentally posted half my original message and I couldn't find a way to edit my previous post. Here's the full text:
Hello all,
I'm having issues with SPA941 phones handling early media (firmware 5.1.8) on the latest versions of elastix and trixbox. I get a ringing tone instead of the early audio I should be getting (other SIP phones and analogue Zap phones play early audio successfully). I've tried changing a few settings which seemed/sounded relevant (including sticky 183) to no avail.
Has anyone experienced similar issues before and/or can think of a reason why I'm getting this? Given it works 5% of the time I can't help being a little pessimistic though.
Thanks.