Phonoland

Soliciting help for a Seeburg L100.
At the end of the record, it has a loud pop. It's been gradually getting louder, and now it's really bad.
I'm assuming that the trip switch is coming into play before the mute switches engage. Maybe?

Well,You are sorta on the correct track--however-- the trip switch MUST "come into play" before the mute switch !
Couple of questions --Do you get the "pop" if you use the rear door reject switch ??
Have you changed caps in the units ?
Do you have a 2.2k 1 Watt on the upper switch stack on the mechanism ?
What is the value of R-186 on the AVC board ?
Ron Rich

Okay, I'm getting confused again.
The first thing I did was open the back remove the cover and looked at the resistor. The resistor is 6.8Mohm.
I put the cover back on, and put in a coin. No pop, either when the record comes to an end, or when reject button is hit.
I'm like wth?
I open the back and loosen the cover plate, wondering what has changed. While doing so, the music gets softer. I tighten and loosen the cover plate again, but there is no discernible effect. Coincidence, or did something just get warm? Now the loud pop is back. And yes the pop is there when the reject switch is used.
I turned off the unit. Removed the cover plates and looked everything over. I see nothing amiss.
And yes, I've recapped all the boards. The other resistor you asked about is indeed a 2.2kohm one.
I"m at a loss.

I would assume,from what yo wrote, that you have a "poor ground" connection--somewhere in the rear door ?
"Tighten/clean" ALL ground connections----
You have the latest changes in the circuit, except you may not have the last one. Look at the trace from pin 7 of the 12AX7 (xv 253) in the 25 PAU, to R-253 (10 meg). If not already there--cut this trace close to the tube, and bridge cut with a 10k-1/2w resistor. Ron Rich