Occasional static sounds like a dirty jack or plug. Jack failure on the R-09 usually manifests intermitant signal or none at all.
Try cleaning it with electrical contact cleaner or denatured alcohol.
I agree-very likely not a jack failure.
from guysonic's site (he prefers isopropyl alcohol):
Clean & recondition noisy mic. jacks with 91 - 99% pure isopropyl alcohol. Repeatedly insert a headphone type plug soaked to the point of dripping (filling the alcohol bottle cap and dipping only the metal part of the mini-plug works well) into the mic jack until any connection noise disappears. Monitor the progress with a set of headphones while the deck is in a record function. Rotating the microphones plug should not produce audible noise with cleaned and conditioned contacts. Applying a contact conditioner to already cleaned plug and jack metal parts