Vinyl noise?

My system is a Scout with SDS, JMW-9, Dynavector 17D3, Sutherland Ph3d, Anthem MCA-20 amp, Rogue Magnum 66 pre and Vandersteen 2Ce sigs.
Lately I am getting "noise" when I play albums and it's occurring at almost the same spot on many albums...but not every album.
It seems to occur about 5 minutes into the album, regardless if its track 1 or 2, and it lasts maybe 15-20 seconds and then it's gone. It does not occur after the initial episode.
The "noise" sounds like the usual vinyl sound when the record is not cleaned. All records get cleaned with my VPI 16.5.
Has anyone else encountered this sort of weirdness? Is it possible that there is a common cause or just a dirty record or a bad pressing? The only change I've made is to add the Walker Vortex vacuum tube to the 16.5.
Thanks in advance.