Avoiding DVI interference on stereo for Macbook

April 25, 2008 8:43 AM

Macbook- DVI question: How to avoid "hum" sound interference on stereo cable with DVI/HDMI cable hooked in?

I tried connecting my Macbook from the DVI port through adaptors to an HDMI cable to hook up to my projector for the first time and the video worked great. The problem is that when I plugged in the stereo cable into the Macboo's headphone jack to plug into my stereo it picked up lots of hum-sounding interference. Any ideas on how to remedy this problem?

posted by tonci to Computers & Internet (4 answers total)

You need to use a ground loop isolator. Here's one on Amazon with RCA plugs. Here's one on Crutchfield with 1/8" headphone plugs.
posted by zsazsa at 8:59 AM on April 25, 2008 [1 favorite]

Piggybacking on this AskMe, if it's cool to do so: Would a similar device potentially eliminate the damn humming sound my home theater receiver has been throwing at me for the last several years? It drives me nuts. Have tried everything I can with the speaker cables to get it to stop, never occurred to me that it might be related to grounding issues with the equipment itself.
posted by caution live frogs at 9:13 AM on April 25, 2008

Most of those hums you hear in home electronics are caused by ground loops, The isolators that zsazsa mentions, whether from Amazon or Radio Shack or practically any major retailer are cheap and effective.
posted by Neiltupper at 12:21 PM on April 25, 2008

Do Macbooks have an optical out? My Mac Mini does, and optical lines (should be?) are immune to ground loop interference. This would require your stereo to have an optical in though, and you could still pickup the hum in other non-optical wires.
posted by philomathoholic at 12:25 PM on April 25, 2008