The specs on the Cambridge Audio Azur 640p state that the MC input is loaded at 100 ohm, 220 mF. From some of the other threads I've read, increasing the loading can actually make the cart sound brighter. Unfortunately, the 640p doesn't have a user selectable load setting. I'd have to physically take the unit apart and swap out resistors and/or caps.
I just wonder what could cause brightness. If it's a bad tonearm/cart match, then I'll never be able to fix that. From what I understand, a low compliance cart generates a lot of resonance, so perhaps the high frequency energy is just resonating all through the light arm tube of the Satisfy and becoming amplified. Or perhaps it's the all-acrylic body and acrylic platter. If it's burn in, then I can wait another 20-30 hours to find that out.
I'm also noticing that only certain albums sound bad. I believe it's the albums that are "cut hot", i.e. the ones where you can turn the volume down all the way and practically hear the song coming straight off the needle. To me this would indicate a problem with resonance. It's possible that the high frequency energy coming off the cartridge is resonating throughout the tonearm and causing treble feedback. If that is the case, I'm not sure how I could ever fix that without getting a different tonearm.