Several points here:

Hypo clear should not cause this type of problem. I have never heard of this issue before this thread, and I have no idea how hypo clear of all things should cause the problem.

Simon is right in his post. In fact, IMHO, Ilford, Kodak and Fuji stand alone in high quality film production, and in full inspection for defects. The record of Ilford responding to issues like this stands above all other companies. It is not likely to be a coating issue.

The last point is the issue of prewet. I agree with Simon, that it should not be necessary, but outside of a lab, with untrained operators or new operators in the lab, I have found that a prewet will almost assuredly clear up any problem with spots or unevenness. That and proper agitation are almost always the culprit.