These amps don't like current limiting. Insert a 10 or 15 amp fuse and power it up (all FETs clamped to the heatsink). Expect a current draw of about 20-25 amps for a second or so when the main rail supply starts.
Is the amp going into protect mode?
Do you still have rail-rail oscillation on the output transistors when you have the signal posted above on the output?
Do you still have rail-rail oscillation on the output transistors when you have the signal posted above on the output?
With a speaker and signal source connected, did you operate all pots and switches in all combinations to see if any audio/static/noise ever played through?