What about the phones Subnet and Gateway,
If 10-12 is set 0.0.0.0 and the IPLA is set right, and the IPLA NIC setup 10-12-11 to full instead of auto, everytime I have had 1 way speech it has always been an issue with 84-26 either the port or IP adress, the port 5080 in the phone is used only for signaling and getting the phone up using 10-12-09 ,84-26 are you speech resources. Im sure you have already checked all of this but everybit helps.
I cant believe you swapped the CPU and you still have an issue Did you put a PZMA Memory on after the initial install, that has giving me some issues once but a good reintialize and reload of the database it worked.
Have you tryed just programing a regular Desk phone using a dlca card to prove that it is or not the Providers issue, or have you tryed just a fresh setup programing the 1 Ip phone and the PRI card, do you have the problem phone to phone as well? Thanks

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