I have shot a with triangle on both my weekend cue and my league cue, and I had the same problem, but only on the league cue, the weekend shooter, I break with also and haven't had the same problem. They are, IMO, the same as lepros, buy a box, and they will all be different hardness from each other. I used a "tip *****er" instead of sandpaper, or other tip roughing tool. I found that seems to be what that tip needs, not to rough it, but to really work sharp points into it, and then chalk it and it seems to work fine for about 1 month, then do it again, depending on how much you play. The other tip seemed to work fine right out of the box. I have used the same tip on other people's cues and the same thing, some miscue, most don't. But when they do, I've used the tip *****er and it worked well. All it is, is a round brass 'dowel' that has about 15 sharp nail points in it and you just press them into the tip, and work it around the entire tip, much like what an aerator would do to your lawn.
Hope this helps.
Dave