is it bad to have it all day on?

I use my DDJ-400 as my PC's general soundcard. I unplug it when turn off the PC because when i turn it off it keeps the power on the USBs and the DDJ stays on.

Would it be bad for it's lifespan to leave it on all day even when i'm not using it? (except when the lights bother me).
I mean leaving it on for weeks