ORIGINAL: archer58
I hate to sound like a broken record, but w/ Mathews bow's Idler lean is the root of most bad tears and tuning difficulty.
I owned a SW and had the identical problem. It didn't rear it's ugly head till I tried to tune broadheads. fortuenately it's an easy fix.
At any rate make sure your axle to axle is exactly 31" on BOTH sides. A twist or two of the yoke on one side or the other should take care of it.
Next set your center shot at about 13/16'' and make necessary adjustments from there.
Your bow is a real shooter and I think this will fix u up.
Bingo, When I used to shoot Mathews, this was the one issue that I learned real quick about, I would call mathews tech support and find out just what the idler wheel lean should be at rest. Some of the mathews are parallel and some are not. I remember on my LX, it had to be set so the line would bisect the string 4 1/2 to 5 inches down. I remember the legacy was straight. I haven't shot mathews for a few years so I don't know what the newer ones should be set at, but that could be solved with a simple phone call to Mathews.
If the wheel lean is off, it can also lead to early serving wear.
Take an arrow and run it on the flat side of the idler wheel and see what the arrow does in relation to the string. This will give you an indication of how much the wheel is leaning and if you are where you should be at or not.
For me tuning starts way before sending an arrow down range, one of the first steps is setting the bow to spec and adjusting any lean as needed when dealing with a static yoke. If it is out, you will never be able to tune the rest!!!!