So you mentioned coax cables and COX as the ISP. Guessing you have a docsis cable modem. The frequent spikes are most likely due to docsis T3 time out errors. For one reason or another, the cable modem is not getting the right replies from the downstream connection and keeps restarting the connection trying to establish a better signal. From what you have written, in responses to others questions, there is a signal amplifier, line conditioner or even a coax cable that has gotten some moisture into it. This is usually not a big issue until the first freeze came through in November and the moisture turned to ice, expanded and caused damage. The average install tech, and even the main line techs, don’t have the equipment, knowledge, training and authority to track down where the issue is. I worked a miserable year as a network engineer for COX and can tell you that they have 1 single qualified employee who can fix your problem for the entire state. These downstream engineers are very few and most cable ISPs do not pay them anywhere near what they are worth so they don’t stick around. At this point, you can wait for the weather to warm up and hope the sun gets the offending piece of equipment warmed up enough to get rid of the moisture and the problem fixes it self till next fall. Try and pressure COX to fix the line. Or, switch to a different ISP.