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Rats, just hit a snag.  In the process of boxing it I noticed that if I installed the compressor LED and it lit, the L5 would sag to half volume and get an almost ring mod sound.  If I switched the comp off it was fine.  Or if I took out the LED the whole pedal was fine (comp works).  Well now I've installed the LED's on the bypass and channel indicators.  LED's work fine but the whole pedal gets the same ring mod sound.  Any idea what's going on?

Voltages look good at -15.04 and +14.98.  I'm using a Line6 adapter.  Is that just not enough to get this thing out of the water, and if so why would it just be the LED's dragging it down?

Have you checked the waveform of the -15V line when comp LED kicks in? The oscilloscope showed kind of saw-tooth wave.I had similar problems with the comp LED and and found 9VAC was not enough to drive the LED. I switched to 12VAC and everything's fine now.

I found the best place for the pre-amp in the effect loop of my KPA.

It's unbelievable, but eventually I found a solution: I replaced the 9VAC PS with a 12VAC and the noise is gone.
Explanation: I think the output voltage was on the border line. We have 100V here in Japan, but the PS was for 120V. That means, that the 9V was really 8V, which is sufficient for a certain current. If the current is higher, then the input voltage is not enough for the 7915 to be regulated to -15V, so it was dropped. Maybe this is far fetched, but sounds plausible to me. Please correct me, if I'm wrong.

The same ones, which were on your Mouser BOM. I replaced C60 with a 220u and then with original value, different voltage to no avail.

Anther strange behavior (which happens only with the internal power supply): when the limiter kicks in, the V- shows ripples of 25Hz as if overloaded. This is audible at the output.I.e. when the limiter kicks in, the comp LED gets on on only the mains hum (half the frequency) can be heard. The voltage over R95 gets to 12V at this point. This would be around 20mA. According to my measurements, the normal load is around 75mA on the V- rail. With limiter, it's 95mA.
That's way below the limit of LM7915 (1A) and my AC adapter (1A). As above stated: external +15V, -15VB: no problem at all. Positive current is constant at 75mA. Any ideas?

I eventually found the problem: Because I couldn't get a proper dual gang  pot C100K for PCB mount, I had to build one from a lug pot. During the tedious inserting of the PCB in to the case, one of the middle joint was broken. After resolder the joint, everything is fine.
Some advises: using MTA .1 connectors for all PCB connections helped debugging. No need for unsolder, resolder etc. Just unplug and replug. Luckily Kevin had the inspiration to use the .1 spacing for the terminals.
As I couldn't get the pot protectors, I used plastic coated tape to protect the PCB from the pots. This was not good enough, so I added some heavy sheets of plastic between pots and PCB. This was effective.

Actually, my observation was wrong. The part does not distort the original signal, but creates an own 4Khz signal 'triangle wave), which is distorted/clipped to a rectangle signal. The frequency varies a little with the setting of the Mid2 pot.
Musically not really useful.

I finished to build this beauty (even my wife likes it - just from the looks ), but I have a small problem: the IC 5 (Mid2) is clipping the input signal. Can someone please compare the voltages to a working one?
I got:
1: 0.29
2: 0.01
3: -0.195
4: -15
5: 0.175
6: 0
7: 0.9
8: 15
The clipping starts, when the pot Mid2 is half open.
CH 1 is working fine and I had too the problem with the direction of LM 7815 and 7915.