I too am having issues with a node on an ISP network dropping packets (Cox Communications). What I did was call Technical Support, and request to speak to the supervisor. I was armed with a trace on the network that pointed directly to the faulty node in their network. What I did was call Hostgator, and opened a trouble ticket. They made sure my site was not experiencing any server load problems, by performing all kinds of tests. There were none so they then recommended I run a report using PingPlotter, and send them the report; they in turn provided me with the link describing the node, which was shown in the report as dropping the packets- I pleaded with the supervisor at Cox to please take a look at the link I had, where on this network-tools.com/.. it supplied the NetRange, CIDR, OriginAS, NetName, NetHandle, Parent, OrgName, and so forth. At that point, the supervisor was convinced and requested that link of mine, and promised to escalate the issue to data engineering. Additionally, the modem did not meet their requirements (tested) with regard to speed so they will be out tomorrow to test and possibly replace it.
I hope this issue is over with soon; I know what you mean. It's enough to drive you crazy.
Also, if you choose to follow the same approach I did, make sure you get the supervisor's name (first and last), and his/her phone number for a follow up!!! Tell him or her you are a Web Developer and you have a deadline to meet; that a good connection is CRITICAL!!! You want to hold them to their quality of service agreement with you!!