Panasonic HMC150 - internal mice - plagued by a significant noise

[Theison]

Hey guys. I just bought an used Panasonic HMC150. It was almost like new (130 run hours). I payed only 1800 $ in a photo shop in Seattle, which i think was an amazing deal? Don't you think?
By the way..
My recorded audio from the internal mice, is plagued by a significant noise. So if any of you got experiences with the sound of the internal mice on hmc150, i would really like you to tell me its an s*%tty build in microphone from new?
I think the build in mice on my dvx100b was better, even though there is also tape noise.

I recorded some sound outdoors (at hmc150) with a low (20%) input setting at channel 1 and 2, and i could hear this noise almost dominating the sound of birds... (with a little exaggeration maybe)
If recording for seriously i use my Røde NTG2 shotgun or/and Zoom H4n - just want to know if my build in mice may be broken?

Thanks
- Theison

 

[TheDingo]

I only use the internal mics for reference, as they are pretty much useless when it comes to recording good audio. ( I always use external mics and sometimes external recorders )

If I was going to shoot ENG style with the mic mounted on the camera, then I would use an Audio-Technica AT875 ( if money was tight ) or a Sanken CS-1 ( if I could afford one ).