I do believe my comment was RIGHT on topic, as it was a suggested reason for saitos to vibrate and loosen mufflers.
Blasting saitos and suggesting one should buy OS instead is definitely off topic.
to the OP (ABELL), try tuning the low end if you haven't already. If you get it in tune good, it is more than likely going to quit vibrating so much that the muffler loosens. Also, tighten them while hot. If not, then when they heat up and expand, sometimes this causes the mufflers to loosen.