Cisco 7970 Asterisk SIP - UPGRADE

Hi everyone,

I’ve problem with upgrading Cisco 7970 to SIP 8.5.4.
I’ve few phones and one was upgreded with success. But when I do all the same with the others I cant do it. Its strange becouse I dont have problems with upgrading that phones to SIP 8.0.3

Anyone knows what might be the problem I cant make them work with 8.5.4?

Maybe there is any better SIP than 8.5.4 which work great with Asterisk ?

Please help.