First of all, welcome to AtariAge.
It looks like there's a problem with a specific component inside the ColecoVision. See here for details on how to fix it: http://www.atariage....ost__p__2018922
Do it yourself or find a friend who can do it for the price of 2 beers, or contact Yurkie here at Atariage.
If you do some browsing in the ColecoVision forums here, you'll find this to be quite a common problem.