said by beaminsfc:My recommendation would be to have the technician bring your modem to the tap (main signal source outside your residence) and perform the same ping tests there. If the problem persists then you know the problem is on Comcast's network and they can no longer blame your wiring. If there is no problem at the tap then unfortunately it is your wiring
If they find no packet loss after connecting directly to the tap, next they should try connecting directly off the drop (the cable going into the box on the outside of your house) and check for packet loss. Most times packet loss are due to the drop.