SWR Basic 350 Red Bass Amp Hum Problem

[telecaster]

This amp has 5-6 volts DC on output and hums. Strangely, with no load connected, there is no DC on the output. As soon as you connect a load, the DC appears. On a light limiter, all PS voltages look correct, +/- 63V for the high supplies, and +/- 15V for the low supplies. Checked PS filter cap solder joints, all good. Measured about .01V AC on both high voltage supplies, and am assuming that's acceptable. Preamp out (EFX send) does not have the hum in it. I checked all transistors and diodes on the power amp board with my multimeter - all ok, no shorts. I welcome any input on what to try next, schematic attached.

[telecaster]

Additional Info

This amp has 5-6 volts DC on output and hums. Strangely, with no load connected, there is no DC on the output. As soon as you connect a load, the DC appears. On a light limiter, all PS voltages look correct, +/- 63V for the high supplies, and +/- 15V for the low supplies. Checked PS filter cap solder joints, all good. Measured about .01V AC on both high voltage supplies, and am assuming that's acceptable. Preamp out (EFX send) does not have the hum in it. I checked all transistors and diodes on the power amp board with my multimeter - all ok, no shorts. I welcome any input on what to try next, schematic attached.

Forgot to mention in my original post - the 0.1 ohm 5W resistors (R23-R26) all measure fine (not open).

[The Dude]

What voltage(s) do you have on the bases of the output transistors (hi side and lo side)?

[telecaster]

Voltages at the Output Transistors

What voltage(s) do you have on the bases of the output transistors (hi side and lo side)?

Measured on light limiter, No Load
Plus side: E = 0V, C = 63V, B = 0.5V (both devices)
Minus Side: E = -63V, C = 0V, B = -62.7V (both devices)

That being said, I found another post on here last night that said these amps cannot be debugged on a light limiter per J. Fahey and Enzo. Since the amp only puts out DC when there's a load on it, do you recommend putting a dummy (resistive) load on the amp and running without the light limiter?