BCM 400 - Phones Light Up Calls Dropped

[Spaznuski]

I have a BCM 400 and sometimes out of the blue, calls would get droped and the phones connected will just start flashing for about 7 seconds, then its back to normal.
I have the unit on a UPS which should rule out brownouts. any one can shed some light on this problem.
Thanx

 

[Crowtalks]

One possibility is you have defective caps in your motherboard.

Also, it wouldn't hurt to power the unit down and reseat the PECs to make sure they are fully secure.

 

[acewarlock]

There is a known problem with the power connector to the back of the Modules being made of cheao crap and any vibrations could cause you to lose power to the module for a sec or 2 and the module would power up again. I had this on only one BCM 400 and Nortel replaced it.