I've been stringing for about 5 years (just for some buddies from the club and myself) and I've had some problems with stringing lately. It's making me doubt my stringing abilities honestly… I just strung a Head YouTek Graphene Radical MP with a Tecnifibre Synthetic Gut 17. Had no problems while stringing. However my team mate played with it for half an hour when the string broke somewhere IN the frame: The same thing happened a while back with a different customer, it was the same string though. This time it happened before he even played a ball (probably laying in the bag). So, what could I be doing wrong? I noticed it's the same string, could it just be a really bad string? Should I check the grommets before stringing if there's something inside that could cut the string or something (like some leftover clay?)? Is it my machine (it's a relatively cheap dropweight, but it's been working for me for over 100 jobs). Or what else could be wrong with my string jobs?? I mean it's one thing if it breaks because of a bad hit or something, but there's clearly something else that's wrong. People never really had any problems with my work until recently so this kind of sucks. Would really like some advice here, thanks!