preamp or power amp problems

[spacecaseace]

I just recently purchased a '78 Rhodes with the Janus Super Satellite speakers (2 large 2X12 towers). Everything seems to be working as it should except: The sound out of the speakers sounds almost as if one of the speakers is blown.  (Distorted- muffled) It only seems to be coming from one of the towers at a time (which ever one is the 'master'). I have pluged other keyboards (My Nord Electro) straight into the speakers and can totally crank the volume without any distortion or muffling. It only happens with the Rhodes and it only happens on the 'master' speaker (the one that the rhodes is directly plugged into).  It is a problem that seems to be getting worse as I play it. I've only owned it for a couple of months and I did not notice the problem when I first got it.  But now it occurs everytime I play. It is definatley more pronounced when the rhodes is turned up passed 5 on the preamp but the breakup happens at even fairly modest sound levels. I have tried two different 5 pin cables. Like I said, I also tried a different keyboard and had no problems so I think that the problem is maybe in the built in pre-amp??? Any ideas?

[spacecaseace]

I have tried a few things since my original posting to try and weed out any other possibilities. I've tried running straight from the accessory 1 jack into the speakers with the same result. I have tried running through a Mackie 1204 mixer so I can send a relatively low signal from the Rhodes preamp and then boost it through the mixer before it goes into the power amp section of the speakers- pretty much the same results except I could get a little more overall volume before distortion. (Not enough though yet) The breaking point seems to be at about a little past '3' on the volume dial where if I play softly its okay but if I increase attack on the keys it distorts. It may be natural distortion from driving the preamp but its only at '3' and its not a 'good' distoriton. As I said above it almost sounds as if a speaker is blown (flabbly and muffled distortion) but the speakers work fine with other keyboards. The pickups are right where I have had them on other Rhodes I have owned but my other rhodes have all been the passive variety.  Do I need to back off the pickups maybe? I have read on this site that preamp problems with this model are pretty rare but sometimes they can have some cold solders or loose wire connections internally. Could this be the cause of my problem? Also my vibrato light does not turn on- the vibrato works wonderfully though- just no light. Could this be causing any sound problems? I love the action and the tone and the vibe of this Rhodes so much (when its not distorting) that I sold my Mark V to buy it. Any advice would be greatly appreciated.

[KCMW]

spacecaseace - If the power supply does not provide the proper voltage to the preamp, it can cause distortion.  Check the cable for proper voltages from the 'repair' section on this site.  4 and 5 pin cables have differnet voltages.