Packet loss on be-15-arsc1.fresno.ca.ccal.comcast.net

Since a recent hardware upgrade that was performed by Comcast in our area a couple of weeks ago, I've been experiencing significant packet loss (up to 85%) from a Comcast router 5 hops away from my CPE. I've tried multiple times to get through to anyone who can help, with no resolution whatsoever. Please please help.