Strange microphone problems

[alintatoc]

I am having hard time when I listen music or watch movies while I have the mic enabled (mute off) in master volume.
When mute is enabled then the sound is good, but when it is disabled then the sound is really bad.

Any ideas what it might cause this issue?

[jagabo]

You're getting feedback from the microphone -- sound being output from the sound card is feeding back into the mic. You should disable the mic whenever you're not using it.

[alintatoc]

You're getting feedback from the microphone -- sound being output from the sound card is feeding back into the mic. You should disable the mic whenever you're not using it.

Is there a way that I can fix this, because couple of weeks ago, before I reinstalled my system it was ok...

[filmboss80]

Jagabo just told you how to fix it (enable mute when not using the mic), but if you are insistent on ignoring him, then you must find another way to interrupt the feedback loop. For example, did you move your speakers closer to the mic? That would certainly cause feedback. (I can't say what the exact problem is, because I don't see your setup.) However, the best fix is the mute option.

[jagabo]

Note you only have to mute the mic in the playback controls, not the recording controls.