What kind of XM radio u have?
I recently finished up my JeepPuter and got it installed in my Grand Cherokee. I had decided to go with an eeepc laptop to power everything, unfortunately it only has a microphone input, and no line in input. I have the line out running directly to an Infinity 4+1 channel amp. Audio playing from MP3's or anything else on the computer are loud and clear, but the XM input I have to max the microphone volume to max and enable the microphone boost to get it to the same level as everything else on the system. This makes the already crappy XM quality almost unbearable.
I'm trying to avoid using a seperate USB soundcard since that would mean I would have to use a USB hub in the back (most of my USB stuff is in a hub behind my "deck"). Are there any quality preamps that are very small and could bring the output of the XM up to microphone levels? I don't know if it made a difference, but I had to install a ground loop isolator between the XM and laptop to get rid of engine noise, even though their on the same ground.
Mic inputs are mono and you need a stereo input.
Might want to go with an external USB soundcard.
The thing with pre-amps is that it can most likely bring some noise or hum in. Yeah connecting the audio to the mic in isn't a good thing.
sound. The sound is based on the intel HD audio, and the app that it comes with even has a place to choose between line in and microphone in, but it doesn't make a difference on how loud the audio is.
Its unfortunate that you're experiencing a ground loop. I had the same problem with my XM Commander when I first installed it. I tried several methods to rid myself of the noise including what you've already tried, i.e., grounded together, ground loop isolator, grounded XM PCBoard to Computer and hedf unit, etc. What finally worked was moving the unit and shielding the unit's PCBoard and RCA cables. Yes the XM PCBoard is picking up RFI and its compounded when you use the RCA out (I patched into my FM antenna and used the FM modulator and no engine noise was discernible).
My recommendation to you is get the external sound card with a decent line in. If that's not an option then bite the bullet and buy some high-end shielded RCA cables (I think I paid $32/pair) and try relocating the XM box to several different locations to find one that reduces the noise picked up.
All my personal installs have been with TabletPCs and until the most recent an external sound card was out of the question so like you I used the mic in for XM. Out of the three different Tablets I've installed, the output of the XM has always overmodulated (too loud for) the Mic line...hmmm.
HARDWARE: Fujitsu Stylistic ST5111w/WiFi and dock, internal Hitachi 500G HD, external 1TB HD, Sierra Wireless Aircard 550, DVD-RW, BoomzBox HD radio, XM Commander, Delorme GPS, Saitek X-52 Pro joystick, BluSoleil Bluetooth, TPMS, FB, Elm327
head unit, I'm going straight from the XM box to the computer thats 8" away using a 1m cable. The only idea I have is that the ACC line has a slightly different voltage than the line directly off the battery and thats what's causing my issues. The ground loop isolator might just be masking the real problem. I just can't figure out what the deal is with the microphone input.
up to the top in hope for help.