I Have lost the Sound on my Beyonwiz T2

[alibil]

Hello all I Need help My beyonwiz T2 has suddenly started recording Channel 10 with weak or non existent Sound 
and only on Channel 10 - Can anyone help - I have done a factory reset and downloaded the latest Firmware but it didn't help - when I am watching channel 10 through the recorder there is no problem the sound is great but once it is recorder the sound is mucked up and inaudible ? "HELP"