Windows sound goes to microphone

[Edward_96]

I am using:
GIgabyte Z170-HD3 onboard Realtek audio (ALC887 codec)
Steelseries Siberia V3 headset

When I play music from Youtube it plays also on microphone to Skype/Teamspeak/Discord etc voice chat. Both jacks are in back io.
When one is plugged to front io same thing happens.
If I use inear headphones in front and Siberia microphone in back io sound wount be sent to microphone.
If I use inear headphones and Siberia microphone both in vack io music is sent to microphone.

Is the back io broken or something? Anyway to fix this thing?

 

[hazzyboy3]

Are you plugging the cable into the right audio jack? It needs to be in the microphone jack and not the headphone jack