3 Power Steering Pumps.....No results

[brimojen]

New Question: Stumped
Sitting at a stop light suddenly power steering(?) started screeching. Fluid at low mark, topped off, noise still continued.
Auto-stethoscope used to pinpoint noise around pump body/pulley.
For testing pulled alternator belt.
Noise still there
Replaced with new power steering pump and serpentine belts.
Exact same noise continues......
Replaced new pump with a pump purchased from salvage yard.
Exact same noise continues......
Tried 2 separate pulleys; ran salvage pump with no lines attached.
Exact same noise continues......
Put new pump back on, took to Nissan dealership for diagnosis.
Service dept. pulled harmonic balancer and determined no problem (incorrectly?)
Service dept. concluded it was the power steering pump
Replaced with second new pump from Autozone
Exact noise continues - no change in pitch etc..
Quick test, no belts no noise...
Replaced high pressure valve.
Exact same noise continues.....
What next? Any ideas help appreciated
This is for a 98 maxima
Video/audio of maxima problem in link below

http://www.youtube.com/watch?v=_D7dERsoEpI

[brimojen]

This was an alignment issue. Evidently exacerbated by Grubbs nissan, perhaps intentionally, pressing the crankshaft pulley on a little further than specs, if my assessment is correct. What caused this is perplexing and my best guess is a shifting (fatiguing) of the adjusting bracket; or wearing at the pivot mount. Shimming, quite a bit since the pulley is farther in, has solved the problem.
Nissan diagnosis was not correct, it was not the pump(s)
I hope this helps save someone from installing pumps needlessly; as I have done.
and paying about $55 for whatever expertise I purchased and character I encountered