Phones seem to be blocked based on MAC

Phone: Aastra 55i
Asterisk V

I have a client who recently has had phones not registering to the phone server. It happened to 3 phones almost simultaneously. The odd part of this is that not all phones are affected. At first I started to even suspect a topology issue, but this was ruled out by a double blind test.

Once this bug hit the phones, it would not register, no matter what was tried.

Here is what has been done and the only thing I can think of is either there is some sort of cache or block tied with the MAC address.

Rebooted the phone server and TFTP.
I did a hard reboot on the phones.
I upgraded the Firmware to current.
I put in a static IP and set the TFTP server to static.
I installed a TFTP server on my local computer and pointed to that (it connected).
I set debug to full and pulled the syslog. It cannot find the aastra.cfg or the MAC.cfg.
It does get the Timeserver though…
I have shutdown every sort of firewall (APF,IPTables,Fail2Ban)

All other phones connect and update fine. I even took another phone and set that phone up in Endpoint and it connected fine. I am running out of extra phones for them though.

Any help on where else I can go?