Exposure around the sprocket holes

[timor]

I'm fairly new to developing B&W (been doing my own film for about a year) and I've recently noticed a consistent phenomenon with my film that is happening across multiple types of film, multiple cameras and multiple 2 reel developing tanks. I get what I think are exposure markings around the sprockets which usually only occur during the first 5 - 10 frames or so (they do not appear on the rest of the roll). Thoughts?

Exposure markings around sprocket holes

Did you resolve your problem ?