I'm hoping someone has some insight on this. I have a JVC SR-V10U which is supposedly the same thing as a HRS7900. Anyway, it has built in TBC and other "professional" features. I am very happy about the video I get out of it. I bought it about 5 months ago and it was refurbished.
Recently when trying to capture an old tape, I noticed the audio went down to nothing and I could only hear hissing. I popped the tape into one of my cheap VCRs and the sound was fine, clear with no hissing. So I put it back in the JVC and I could hear the audio (although low) but then over the next 10 seconds it faded and you could only hear the hissing. If I stop the tape and restart it, same thing, you hear it at first then it fades. I then noticed later on the tape when I switched to another video camera (thankfully on the tape I mentioned I was using a different camera), the sound is fine. Later when I switched cameras again, same problem. There is considerably more video noise in the camera I was using where the audio problems occur. But again, when I play these sections in the cheap VCRs they show this video noise, but the audio is fine.
So it appears to be a function of the particular camera I was using when taking the original footage, and this VCR. No matter what settings I use on the VCR (TBC, no TBC, stabilization, etc) the effect is the same.
I know this is a convoluted problem and there may be no answers, but I'm stumped and fishing here.
any clues?