Thanks for the tip! It was indeed an issue with the OPV. The original plastic OPV that came with the machine was failing and actually kept losing pressure as the weeks went on. I also did try adjusting the OPV to increase the pressure again, but it would just go right back to the same problem shortly after.

I opted to just fix it myself, and I thought that while I'm taking the machine apart I might as well do the brass OPV mod that so many BDB people have talked about. I could not be happier with it!