Hey all, Weird issue here. Audio works fine in all cases except for one while using a Grandstream GXP2170 phone tied to my extension: Call from external phone to Queue (works when dialing direct extension) Audio from Grandstream is heard properly on external phone Audio from external phone (Verizon / T-Mobile Smartphones) is not heard on Grandstream Our firewall appears to be setup properly, and audio works fine in all other forms (3CX app on OSX or Android on same extension). It just isn't working from the smartphone to the Grandstream phone when the call has been made through a Queue, specifically. The audio works just fine from the smartphone to the Grandstream when call is made directly to the extension after calling the IVR and punching in the extension number. Any thoughts?