Is it.................Mold?

So, in the last six months, I've twice found some wierd gunk in my picnic taps when cleaning my beer lines. I THINK that both times, it was probably a little trub, stuck inside the dispenser, that MAY (it's hard to tell for sure) have grown some mold on it. The first time I wasn't to suprised, as the beer had sat for a long time undrank (Feusals I think) and I was dumping the keg. However, I just cleaned a dispenser from a great IPA I just finished, and was suprised to find somthing similar.

This ever happen to you?

Thanks.