Aile..aelie...ae....aliens!

 

pls use other spectral analyzers, with a range at least up to abt 50 khz to see more.
It might be 22,05khz or 24khz (half frequency of 48khz or 44.1khz sample rates) switch to 96khz and check if the spike changes to 48khz. It might be bad "shielding" on the motherboard or cables.
I use this MB for such reasons : http://www.gigabyte.us/MicroSite/335/images/audio.html
Computers produce a lot of high radio frequencies which can fuck up the audio. These can also emit into USB and external interfaces.
Try ferrite core blocked USB cables: https://en.wikipedia.org/wiki/Ferrite_bead

I hope we can find the "GHOST", maybe electronic engineers here on this site can add their opinion. I am abt 30 years out of this job...
these are just some thoughts i had when i saw these oscillating spikes.

 

funny, because i already have this one, and the audio interface usb cable is passing through that already...

 

i think that your best bet now will be tryin' another soundcard... if possible, obviously...

 

I'm sorry I have to say this, but I think your MobilePre must be going dodgy, MrLyann.

Maybe some condensers or ICs are starting to fail. I'm just trying to be objective.

 

Life is too short to troubleshoot M-Audio gear. No offense intended; I've owned some myself, but never regretted moving on past the initial sting of clicking "Add to Cart" for something better.

In other words, use it until it becomes an actual problem and then ditch it.

 

All audio interfaces have noise-floors. Some higher than others (including the M-Audio brand). ;)

 

Last edited: Mar 23, 2016