Hi everyone, I have a TiSp sx strung with bg68 ti at 22 lbs. After only 8 sessions the 2 main strings in the middle broke. I've since had it restrung at another stringer who told me it was not strung correct. (there were 2 extra lines running cross at the bottom-this I was told was not yonex spec) Could this have been a contributing factor to the premature breakage? Also would this affect the sweet spot?