Cleaning PCP baffles

I have had my first PCP for just over a year. It's a Benjamin Akela .22. I LOVE IT! I've put at least 1500+ rounds thru.
It has been very accurate so far. However, I cleaned the barrel and it was still doing amazing, until I noticed it was starting to shoot to the left. I removed the shroud and cleaned the barrel again. Then I dumped out the baffles to give them a look..... YUCK! A lot of black powdery stuff came out and the baffels are coated with a fine powder.
Is this normal? How do I clean them? What are they made of?
Thank you in advance! ;-)