Whine on USB mixer only when Aud is monitoring

to be clear – I’m NOT monitoring Audacity through the mixer… I’m just monitoring the microphones (or keyboard) hooked to the mixer. I do NOT hear Audacity output on the headsets. But I do get this whine (NOT very loud, but present) – and only when Audacity is monitoring or recording. If I Stop Monitoring, the whine disappears.

I may know what the mystery link between Audacity and the mixer is. This is a reading from the web site…

You can also monitor back from your computer through the same USB connection.

How do your instructions say to do that?


Sorry, Koz, I don’t understand your post. What web site is that from? I couldn’t find it online (googling your quote just brought up this post).
I don’t have instructions that tell how to do that.


Sorry. I missed a step. That’s a quote from your mixer instruction book – on-line version.

[Booming kettle drum sound]

They claim a condition whereby the computer will send sound back to your headphones. They’re clear about that. So that’s the sound pathway you’re probably hearing and you may need to go to the maker of the mixer to figure out how to turn it off.


it seems like sound is leaking back through his device while monitoring
and interfering with his direct monitor signal

there may not be a fix
this just may be leaky electronics
eg imperfect impedance blocking the signal path – not infinite

aha! Thanks for pointing out the online manual; I was working from the skimpy printed version. I’ll check it. Thanks guys! I’ll let you know if I discover something…



I went back to look and it doesn’t say that any more. References to monitoring the USB return pathway vanished.

Perhaps enough people complained that it didn’t work right or at all.


puzzling! I tried unsuccessfully to download a manual for the mixer… and I wrote their tech support ppl; no answer yet.

the alesis site is bogus
wants all my personal info to get to the dl page
then it died and never showed anything

i would never trust a product when their web is so screwed up

try downloading the manual from zzounds
it was larger than the one alesis said they had to dl
so might not just be the quick guide but the real deal

got the manual
does this fit your connections

Simple Recording Setup
In this setup, you connect your instruments and microphones to
the mono and stereo channels, making sure to properly set the
level of each channel. To record directly from the mixer to a tape
deck or other device, connect the device via the 2-TRACK OUT
jack. …
For monitoring you can connect the CTRL RM OUT jacks to a
speaker or headphone amplifier, or just simply plug headphones
into the PHONES jack.

they give this in tips
Audio signal carries an
unwanted hum.

Interference from appliances
such as air conditioners.

Not using TRS cables. Make sure you are using 1/4”
TRS cables.

USB audio has crackling or
glitches, or audio
plays/records at incorrect
USB hub may be in use.
Computer configuration may
be incompatible with USB
If you are using a USB hub,
disconnect the Multimix from it
and connect the mixer to the
computer directly instead.
Certain USB chipsets have
design limitations or IRQ
assignment restrictions that
must be resolved before audio
can work correctly on them.
See your USB chipset
documentation for further
information if required.

I had a similar experience with a Peavey PV8USB. I do recordings in my church, and found an annoying whine in the headphones and speakers during recording and during playback. The whine was also present in headphones and speakers when the system was idle. At first it seemed to be intermittent, but I realized that it was always there, sometimes very soft and sometimes loud. I could remove it from recordings by using the ‘Noise Removal’ procedure. The whine was always there using the USB connection to the computer, and never there when I was using analog connections.

This eventually led me to examine the USB cables. I have a box of a couple dozen USB cables from 1 meter to 4 meters long, and I soon that the noise was directly related to which cable I use. USB-1 cables always gave an unacceptable whine, USB-2 cables gave a much lower level of whines. Within each of these two classes, shorter cables gave a lesser whine.

My cables come from a wide collection of sources, but the two quietest cables originally came with (1) an external disk drive adapter and (2) a Shure X2U microphone adapter. The noisest cable came with an old printer.

I also found that the noise could be reduced by putting a ferrite around the cable, but I don’t yet have one properly sized for USB cable.

I shopped around the stores in my area and found two cables that seem to be top quality - a Monster cable from Guitar Center that was 3 meters long and a Rocketfish cable from Best Buy that was two meters long. I bought the Rocketfish. The whining noise is completely gone; in fact a few other very low level noises that I wasn’t really concerned about also disappeared.

I have ordered some ferrites properly sized for USB cables; when they arrive I try them and post the results here.