Have a Kxtda 600 with 4 cabinets total

Analog sets just stop ringinh for no reason
Reset the power supply and it straightens out
have replaced all power supplies and the isu\sue keeps popping up
Cables and jacks are fine and the sets seem to straighten themselves out when re-connected.

Any ideas

do you have a lot of slts in a ring groups?

No Ring groups at all used

I’m going to assume that you did a load calculation and have the proper size power supplies in the cabinets. I've seen this happen with the wrong power supplies installed.

Absolutely. The vendor we deal with had Panasonic on the line and discussed it before they were sent

Are the analog phones on an expansion shelf?

This is a work camp set up
The 1st shelf has a combination of analog sets for rooms and digital sets
Shelves 2,3 and 4 are all analog sets for rooms

I'm at a loss as to what this problem might be. If all the analog extensions were on expansion shelfs then I suspect that there might be bad Bus cable(s) or card(s). When the Panasonic dealer was on site, did he look at the error log and see any that might point to this trouble and tell Panasonic tech support what they were?

We have sent them the config files as well as captured diag files while testing the phones in question
just heard that the info is being sent to Japan for them to have a look as well
It's been 3 days since all the power supplies were changed and we haven't had a problem, knock on wood.
maybe we need a priest