I have an isolated VoIP VLAN/subnet that I'm using for my corporate telephony but am experiencing a bizarre behavior with my network which is a mix of Cisco IP79xx phones (enterprise grade) and Cisco SPA50x phones (lower quality consumer grade.)
Both sets of phones are on the most current firmware, as are the Cisco phones, and the phones can all initiate a 'ring' to the other models. However, the SPA50x phones can ONLY transit/receive voice traffic to other SPA50x phones, and the IP79xx phones can ONLY transmit/receive voice traffic to other IP79xx phones.
A SPA50x phone, when picked up, can't receive or send voice to an IP79xx phone, and vice-versa.
Would this have anything to do with the OUIs defined in the 3548P firmware? The switch is on the most current firmware (2.0.0.53) so I'm stumped why the phones can't ALL connect and tx/rx voice packets to each other?