Audio Ticking noises in H.264 .mov

I have a quick question on some noises I've found sitting in an H.264 .mov file that I recently shot.

I picked up a cheap hd camcorder with the simple hopes of picking up some 'b' roll scenes every now n then, and perhaps this won't be feasible w/o a higher expenditure. First off, the scenes are not critical, and I don't / won't expend much energy on cleaning up things, but would be nice to be able to use with some ambient noise at a low volume merely for efx. I can use the footage w/o the audio, and will if that's what necessary.

Have any of you noticed any residual noises in H.264 footage? This noise is random at best, and has some kind of "ringing" type noise which precedes a "ticking" noise. This ticking noise is rhythmic... tick tick .... tick tick tick.. and so on.

I'm using class 10 cards, 20mb/s so I don't think that the card would be a problem, yet.. I'm wondering if this ticking might be some kind of "lag" or 'buffering' on the card.

Any help would be appreciated.

regards.

If it moves . . . Shoot it!