You might get lucky if you look at the other end of the com cable to see if you have the same thing going on with the wire breaking.
This is a good example of cutting too far into the wire when stripping. You knick the copper wire and weaken it. Seems ok when wiring up but over time may break from movement.
Yes you are exactly right. I do low voltage for work...Voice-Data and deal with almost this exact size wire and that is something to be careful of. Unfortunately I did look at the other end when I found this and it is still pretty solid. But you helped me by leading me thru the steps and found this on the way. Many thanks. I replaced a Cell that didn't need it as it looked really clean before I tried cleaning it but if was almost 4 years old anyway and probably good that I went ahead and replumbed the new cell. Now I know it "shouldn't" be the next thing I have to fix.