the cause is using the mixer incorrectly, or mixer is junk, IDK,
now idea at all what system parts are there, not a clue here.
in the mixer, uncheck microphone.
Computers can be set up 1000s of ways, you know?
Not even a clue at all what PC< desktop or laptpo
no clue at all. just vague DJ bla bla....
answer is so will pure generic electronics (im certified tech. retired)
Most PCs of all kinds have sound card, or built in. (or just 1 chip)
be it a destop or lap top,
my PC has a sound card, (fancy,) DTop,
with 7 channels and all that stuff.with matching powerful software.
on a real desktop with a real sound card it has many jacks there
not just 2, (mic/speaker.,)
mine has line in, and line out. and many others for speakers,
there are 2 ways to record
1: using and external , say Mp3 recorder. (and 100 other ways )
2: and using the built in sound recorder in windows, do you have windows. you never said that nor which windows
the 1st choice is hardware, pure electronics, in fact tape recorders worked there for since first one made, using line in. to recorders.
choice 2, is software, you can buy a APP to do that, that is better than what Windoz offeres.
see that lime green wire?
the top sound cards all have special softeware
that has a super fancy MIXER, the mixer allows you to mix
anything you want. with a click of a button
if you dont have good sound card or matching software
all you get is windows basic crippleware. weak and very limited.
so next time tell the helper what you have.
fully and get 10x better answers.
here ill wet your whistle, on what can be done.
you want 2 CHANNEL STEREO recorders.
or even TOSLINK connections.?
How good is your source music, ? if poor then use cheap hard/software but don;t expect windows to do this well.
if running windows 10 go to the MS windows, STORE,
and buy a better audio software package.
ideas, are endless in recording
hardware super good. or better,
last is fancy app software like this.
I use this
it does it all. for near nutt'n.
GOLDWAVE (ive had it for 20 years too)
the word Disk Jock is a persons or is one of many hardware products, not stated by you.
is it this. old box? by maker NUMARK?
in the above jack 15 line out goes to sound card, LINE IN.
then in the PC you play or record off of LINE -in in the PC.
if you dont have a real PC with a Real sound card
this can be hard, using the MIC as a line input will cause
huge overload saturation of the mic amps, and sound like H3LL..