Do you run multiple audio programs simultaneously ?

[XPcentric]

and is it any harm ?

for example playing a video with sound and audio music in the background.

 

[Merthyrboy]

I don't know if it's any harm but why do you watch a video and listen to music at the same time?

 

[iVikD]

I suppose that as long as you're not overtaxing your speakers, it should be fine. I don't think it's good though, as things playing over each other might create some sort of distortion and blow your speakers. That's just my speculation though.