FS-8520 Prints fine, Copies are way too bold

[DougMoney]

I have an FS-8520 that the prints look great but if you copy through the document feeder or on the glass the colors almost look like there is black getting in the colors. The letters look like too much charge where you can see ghosting around each letter. The black print looks more like bold print. If I manually turn the exposure down to -3 the copies are pretty close to normal. I believe the problem is in the ISU. Any help with diagnosing this further is appreciated.

Thanks,
Doug

[Ropariva]