Humming noise

[LichE30]

Good morning . I having a problem when I connect my new stereo on my e30
And I turn it on am hearing a humming noise . Can some one help wha I did wrong .

[htown318is]

perhaps check your ground(normally black), maybe even power source.(red or yellow) thats the only thing that gave me a problem if I didnt take my time on those.

disclaimer: im no pro.

[Gregs///M]

Try connecting one speaker at a time, perhaps you have a short or a blown speaker causing the noise.