33% is close to saturation, but that should not really be an issue because the prints must go through all the clearing and washing steps after that, and PO is fairly readily soluble. The problem with being that high is that you will get crystals in the solution, especially if you use it warm or hot. This can cause damage to the print surface as you pour it over the print, etc.

I've never had crystalization problems on my prints, so I don't know where to start to solve the problem, but you may want to look at the steps nearest to the end; the wash and the clearing steps. Are you positive you washed long enough? What clearing baths did you use? If you put the print back in water, does the crystals clear, or do they remain?

Most everyting that we use is fairly soluble in H2O, so my initial thinking is that you may be able to salvage the prints by washing longer. If I had to guess, I would also go with not enough washing after the clearing bath is resulting in some remaining clearing bath chemicals in the paper at the most likely candidate.