whine whine whine

spoolup · 06-30-2009, 03:52 PM

hey guys,
little issue with engine whine.
in know it's a common thing on carpc's but the scenario is a bit odd.
i'm running my mobo's audio out thru my headunit aux in.
the whine is "selective"
sometimes it will be there sometimes it won't.....
i run the 5 foot wire thru a ferrite magnet and the distance between audio out to aux in is a foot apart.....
any ideas?
thx

i thought of a loop isolator, but it seems overkill

soundman98 · 06-30-2009, 04:04 PM

it might be related to another device that you are plugging in, could you list your dc-dc power supply, and head unit brand/model#?

spoolup · 06-30-2009, 04:10 PM

i got n m1atx powering a dual core atom (intel) 1gb board. powered off the battery and the switch is off the headunit's harness.
headunit is blaupunkt brisbane sd48.
the only other devices plugged into the pc are usb extension to the screen and gps.

sound from the headunit is superb when on radio.
once aux in is selected, like a said, it's a hit and miss.....

jpinkerton · 06-30-2009, 04:37 PM

Outta curiosity, do you have the power lines to M1ATX alongside the audio?

spoolup · 06-30-2009, 04:43 PM

don't think so.
i'll take the cover out tomorrow and let you know.
but i think they were on the opposite sides of the voompc case.
but the power lines are next to the audio jacks....

pathfinder123 · 06-30-2009, 05:10 PM

Whine, crackles and other noises are generally caused by earthing problems.
Fit a ground isolator. At less than £15 it's a no brainer.
Despite taking a lot of care with my installation, I still had a lot of noise.
Fitting an isolator took 5 mins and got rid of all the noises.

Cheers
Stewart