Hard to say for sure. What’s a little unusual is that you said it starts where the bottom limb attaches. I think I would call the manufacturer and ask them first before doing any more shooting.
For the past 20+ years I’ve used cedar and spruce arrows for deer and small game. Always use 125 grain broadheads and usually two blade Grizzlies or some free three blade woodsmans I have a stash of. Usually my finished weight is around 600-650 grains. I will shoot any type of arrow but it seems...
It could be your release. Pulling your hand away from your face. I shoot with a glove and even though I don’t pull my hand away, sometimes my arrow goes to the side a bit if I don’t hold my thumb and pinky together on the release hand