I have an original DICE and have returned one due to this issue. My replacement occasionally will have the high-pitched whine or a hissing noise. I have found if I unplug the white plug connected directly to the DICE unit and then replug it in, it usually clears up any noise. I have to do this every couple of months.

I want to try the alternate grounding - makes sense to ground it closer to the unit.

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2001 X5 3.0i (PP/WP/AP) Traded at 213K miles
RARE White on Black - Why does everyone get Tan??
First E53 with 215s on XOutpost!!