Pop Star Slouchy Hat

I’m wondering if anyone else out there has worked on Leisure Art’s Pop Star Slouchy hat? Currently, I’m working on a practice gauge for a size H hook (as recommended by the label on the yarn I’m using even though the pattern itself lists a size I hook) and at about round 3 or 4, I’m starting to experience some ruffling of the fabric. It’s my understanding that is usually due to increasing too much, but, I also understand that due to the nature of certain types of stitches, the ruffling will happen anyway. I’m just wondering if I’ve increased too much, is it due to the hook, or is it to be expected?