T46G lock up issues

[tysnweiss]

I have T46G phone with (4) EXP40's attached with two power adapters connected to the EXP40. Periodically when the receptionist transfers a call to an extension on the EXP40 the transfer goes through but the T46G locks up. When this happens and you attempt to press any buttons nothing happens, no dial tone, calls ring to back up receptionist and nothing on screen changes for about 30 seconds and than the phones comes alive and you can use it.
The also have stated that when they come in first thing in the morning the phone is locked and wont do anything and they have to power-cycle phone to get it to work. I have included hardware and firmware versions for both the T46G and the EXP40's. Thank you in advance for your assistance.

T46G
Hardware: 28.1.0.128.0.0
Firmware: 28.80.0.70

EXP40
Hardware: 66.0.0.0
Firmware: 7.16.0.0