Spectravox noisy?

Hi,

I have a new Spectravox, and when I patch a simple marimba sound, a lot of the internal white-noise sound comes through even though I have the mix knob all the way to the left.

Could a few of you let me know if this is how your unit sounds… so I know whether my unit needs repair?

Here is an audio/vid clip of my unit doing the marimba sound. (I am adjusting the Decay of the envelope during the duration of the clip). The pinged filters create the marimba sound, but then the noise bleeds through and trails off according to the envelope setting.

https://www.youtube.com/watch?v=kQFyHkAp4-Q

Thanks much for any help.

-Jed