Check the tracking on the blade and also the tension. I think you have a little drift going on. One other thing to consider is using a straight edge to draw a cut line so you can see if it is drifting. Your blade is a good one. I'd also check on line for videos of resawing with that saw. I try to center the blade so the back of the gullet runs on the center of the tire. A 3/4 blade is pretty exacting on tracking, but if it isn't tracking right, it's going to drift. Also, feed slowly. Let the blade do the cutting, not you pushing the piece through the blade. I have done some resawing with my 14/12 with a Laguna half inch, 3tpi blade centered as I described and with the line drawn on the workpiece (about 18 inches long, and it came out less than a 16th off. I also made sure the blade was 90 to the table and that the guides were about a quarter inch above the workpiece.
I have a Resaw King blade for it, but the half inch really did a nice job, so I'll save the king for some harder wood. Watching the blade track the line was very helpful.
I also have a small, 12 inch bandsaw, and although it is not particularly powerful, it will resaw with a half inch blade. And using the same approach to tracking, it doesn't drift either, well, as long as I don't rush it.
I recall finding a video on YouTube about setting up the saw, which also suggested a method to deal with drift. There are 14 videos in this series and I think this is the one that talks about tension and drift. Very helpful.
You can view all the rest at the same site. For someone just buying the 14/12, the videos make setting the saw up easy, from uncrating to assembling the various parts, including the mobile stand.
I really like the beefy bearings on this saw, and the cool blocks are much easier to deal with than Carter style guides.