All calls are recorded so I can guarantee they are not lying to you, that can get them fired. That being said, if you disabled iIPv6 and there was no change, then we know what's not the issue. I would hazard a guess that you are not seeing input drops, but seeing retransmits. Can you go to 192.168.100.0 and take a snapshot of them. If you are having a levels issue and seeing a lot of re-transmits, that would do as you a5re describing. Also, if you have cable connections not being used, try to remove excess splitters, and replace barrel connections in wall plates and swap the cables out. Sometimes those actions can help and cure the problem as well.