Accord 2003 AUX Input Issues

[MichaelNelson]

I picked up an AUX input box from Grom Audio awhile ago, and installation went fine. However, I'm having two issues with the unit that their support won't get back to me about, and so I would like to ask your community if you've ever heard of either or both of the following:

 

1) There's a faint ground loop that results in a high-pitched whine that varys with the RPMs. It's mostly quiet enough to ignore, but I still would really like to eliminate it. I've tried a Ground Loop Isolator, which did nothing.

 

2) Out of nowhere, usually about 5-10 minutes into use, the audio volume will simply drop to a level about half of what it was. Restarting the stereo usually resets it. Issue with the stereo, or the Grom box?

 

Thanks in advance for any ideas.

 

Car is an Accord 2003 EX with navigation.