Highly unlikely, the upgradeing is only affecting the transmission system and at which freq. it tops out at.

The problem you have described can really only have 2 causes

1. The equipment in the house being bad (tv or cable box)

2. A problem at the hub and/or headend themselves.

With a digital signal regardless of the strength or qualtiy of the signal on the transmission system you would not see any changes in color/clarity. What you would see is pixelation and breakup. Its also possible to have sync issues with audio/video but that is rare. The only 2 items that affect the color/clarity of the picture are the box/tv at the house and the modulaters at the headends/hubs.