I have a Avaya Definity PBX with a Cajun P580 core swith, using the
Avaya 46 series IP phones. I am getting errors on certain IP phones
that say "error" registering # to reset.

1- I know the phone is getting an IP address from the DHCP server.
2- It kind of floats around the 100+ extensions I have.
3- 3 or 4 extensions are effected weekly.
4- I have changed phone hardware and keep experiencing same problem.
5- We have recently replaced blades 1&4 in the Cajun P580.

Any help you can give me would be appreciated. Thanks