I've been trying to get into srt for a few weeks. I'm using a rope runner and 11mm edelrid static line. After a few uses I'm noticing the edelrid is getting permanently flattened. So I tried it on half inch Samson arbormaster and noticed the same thing, but not as pronounced as with the edelrid 11mm. Is this normal for the rope runner? Do all mechanical devices do this? Anything to be concerned abouf?