I'm quite sure these machines all suffer from old image units causing dark copies & prints. We buy them off lease, refurbish & sell. Common denominator is most print too dark. Anybody know what adjustments we can make to lighten up either individual or all colors? We do the gradation & stabilization adjustments. Several customers bought for 99% print only, rarely ever copying. The image units have like 10% to 30% on them and have not been chipped. Colors seem to be so dark they bleed, or are fuzzy, like overtoned when closely examined.