Scrotum Hair Fungus?

[ds2008]

Ive noticed for probably 5 years now that some of the pubic hairs on my scrotum are discolored and look like there's a thin layer/skin of fungus or bacteria growing on them.  The normal color is black and these particular hairs look like they may as well be blonde but its definetely noticable that there is a coating of something on these hairs. Its enough to feel like I can pinch my fingers together and scrape the substance off the hairs with my nails but it doesnt seem to come off easily. I usually use exfoliating gloves or a loofa which are only for my use but I have noticed this for years and can't seem to get it off during normal showering and most of the time it just goes un-noticed.  The only hairs that seem to be affected are on the right side of the scrotum but there are some on the other side also. I have no physical pain with this problem though throughout my 4 years in the military I have been diagnosed with epididymitis multiple times though nobody can seem to tell me why or how to make it not happen again. I have been tested for STD's multiple time and have been married to the same woman for nearly 3 years. She has also been tested and is negative also though I am quite sure that this is not in the STD category at all.
So I'm just writing to ask if this is a common thing seeing that the scrotum is usually in a dark, moist environment, probably a favorable place for fungus/bacteria to grow.  It doesnt grow out of control or show ANY signs of progression but a close look makes it look like these hairs are growing this way out of the scrotum.  I have shaved my pubic region and scrotum multiple times but it keeps showing up which makes me think that only these select hairs are growing this way.

If anyone has any input, comments, suggestions, or answers please let me know. This has gone on long enough without telling anyone of the problem since I feel that it is nothing to worry about but it would be nice to get some peace of mind.  :)   Thank you to anyone who can help!