mine was doing the same thing, keefie has the solution for 90% of the saws
i ended up pulling off the lower blade chuck to take a look at it and i can see why the blades kept getting pushed out, previous owner(s) had to be cranking down really hard on the knob as the walls of the block were pushed apart so far that only the very ends of the flat parts of the knob and the set screw would touch on the blade and when it got tightened it would just push the blade out and bend it and now with the new lower clamp installed it works great!
i ordered the parts from Ray on a Monday and he had them in my hand on Thursday so once again great service from Seyco.