Petzl - Rumba 8,0 - Half rope tested

One of the double rope we bought in the summer of 2021 was damaged very badly, after the first uses.

We used it to climb some trad routes They were just simple, ordinary routes, and we did not make any falls in the rope. Nor did we have a in any way a deviant descent or something like that. Still, after 4 climbs (on granite and gneiss), we were stunned to see that one of the ropes, the red one, had deteriorated in a bad way on several distinct places. We had abseiled only once the days before, for 20m in granite, ropes through a good standard metal abseil ring, no problems in pulling the ropes down. After that moment, we abseiled 2 longer pitches in gneiss.
Only the red rope was damaged, the blue one was fine.
I have been climbing for over 30 years, and I have never experienced anything like that with a rope. I am convinced that there was something wrong with it to begin with.