Hitachi VM-D865LA video camera Sound not working

[P&L]

I bought a used Hitachi VM-D865LA Digital 8 movie camera. When I
record video not sound is played back just a faint scratching sound.
I can tell the microphone is working when I have it hooked up to my TV
I can hear sound fro the camera microphone on the TV speakers.

any idea what to check?

Thanks,
Paul