If you're seeing packet loss without T3 errors, it could be node saturation. However if you're seeing packet loss with T3 errors, the problem is more likely noise ingress on the upstream band. You'll need to have another tech come out and check for packet loss at the tap. Even better if they have the proper tools to scan for noise on the line but it seems like most techs don't have that tool. You might see others posting similar problems on the forum, but unless they live on the same block as you it's not the same problem. It's just one of hundreds of problems all over the network.