Reading the DSLReports thread referenced below, it appears to be the same problem -- an open neutral on your electrical service. Since your electrical service neutral is open, the coax is serving as the neutral return path and is carrying a lot of current.
The only way coax gets that hot is if a lot of current is running through it -- which is not normal (under normal operation, the current is miniscule).
This is a life safety issue and requires immediate attention.
- Call your power company immediately and report you have an open neutral, which is causing your cable coax line to carry current and catch fire. They should respond immediately.
- Do not touch it. You don't want to become part of the return path for your power service.
- Don't let a cable technician touch it -- same reason, it's an electrocution hazard.
Let us know what happens.