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Sansui AU-5500...terrible distortion from both speakers.

If I remove either F04 or F02, the DBT does not indicate a short. If I replace F04 and F02 and remove F03 or F01, the DBT indicates a short.
 
All that is confirming is that the fault is on the right channel.As Leestereo said short gone with the right channel output transistors removed?
 
The lack of distortion via headphones would indicate that the driver stage is fine. The problem is within the output stage; test the resistors R47-R50 and the emitter resistors R69-R72.
 
R47-R50 all tested good. R69-R72 with meter set on ohms,R69-00.8ohms, R70-00.7ohms, R71-00.8ohms, R72-00.7ohms before subtracting the 00.3ohm resistance of the meter probes.
 
My best guess is that although they test good at low voltages, the output transistors on right channel are failing/damaged and when subject to full rail voltages they draw too much current.
 
Testing with a curve-tracer could be useful. If you don't have one, then its easier and better to replace with new.
 
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