Bizarre noise issue

[relative q]

So I switched laptops the other day, and now my all my equipment is making this midrange hum that I can't track down. If I plug headphones into the laptop, I don't hear it, but the moment I run the output of the laptop into my mixer, I hear the noise. The odd thing is, both the internal sound on the laptop AND my MOTU 828 are making the noise, the MOTU a little more quietly. It makes this noise regardless of any volume settings. What the fck is going on here? Is this some sort of weird HDD interference I'll never be able to get rid of?

If it helps, hardware is as follows:
Dell Inspiron 6000 laptop
MOTU 828mkII interface
Fostex PM-1 monitors
Behringer UB2442FX mixer

Before some of you yell at me to buy a new mixer because Behringers are crap, I'd just like to mention that I never had this problem with my old Thinkpad T22 laptop with the same setup.

Anything anyone can suggest would be most helpful. I'm having serious issues ignoring this noise.

[skept]

So I switched laptops the other day, and now my all my equipment is making this midrange hum that I can't track down. If I plug headphones into the laptop, I don't hear it, but the moment I run the output of the laptop into my mixer, I hear the noise. The odd thing is, both the internal sound on the laptop AND my MOTU 828 are making the noise, the MOTU a little more quietly. It makes this noise regardless of any volume settings. What the fck is going on here? Is this some sort of weird HDD interference I'll never be able to get rid of?

If it helps, hardware is as follows:
Dell Inspiron 6000 laptop
MOTU 828mkII interface
Fostex PM-1 monitors
Behringer UB2442FX mixer

Before some of you yell at me to buy a new mixer because Behringers are crap, I'd just like to mention that I never had this problem with my old Thinkpad T22 laptop with the same setup.

Anything anyone can suggest would be most helpful. I'm having serious issues ignoring this noise.

this seems to be a problem with dell notebooks. a solution that i was told by a friend is to use one of these:

http://www.radioshack.com/product/index ... age=search

it converts the three prong to two. i have tested this and it does work. i do not know why it works and i cannot tell you if it is a good or bad idea to do this but it definitely works.

[skept]

So I switched laptops...

hey i just noticed you are from pitt! i live in canton, ohio. been out to pitt for many wicked parties back in the 90s. cool to see you here!

[relative q]

So my electrical engineer roommate figures that it's just poor isolation within the laptop. I guess I'll just have to live with it for the time being.

Skept, you wouldn't happen to know a dude named Aaron Clark from Canton, would you? He lives and DJs here now. Good dude.

[fl0w]

many laptops are noisy when the PSU is plugged, and become silent when operating on batteries...

[skept]

So my electrical engineer roommate figures that it's just poor isolation within the laptop. I guess I'll just have to live with it for the time being.

Skept, you wouldn't happen to know a dude named Aaron Clark from Canton, would you? He lives and DJs here now. Good dude.

you should try that ground thing, they are cheap so no big loss and easy to get at radio shack.

hrm.... dunno if i know him or not. i know/have known so many kids from northeast ohio and most of them only by their first names. and i have known quite a few aarons. what does his spin, what is his dj name?

[New Guy]

So I switched laptops the other day, and now my all my equipment is making this midrange hum that I can't track down. If I plug headphones into the laptop, I don't hear it, but the moment I run the output of the laptop into my mixer, I hear the noise. The odd thing is, both the internal sound on the laptop AND my MOTU 828 are making the noise, the MOTU a little more quietly. It makes this noise regardless of any volume settings. What the fck is going on here? Is this some sort of weird HDD interference I'll never be able to get rid of?

If it helps, hardware is as follows:
Dell Inspiron 6000 laptop
MOTU 828mkII interface
Fostex PM-1 monitors
Behringer UB2442FX mixer

Before some of you yell at me to buy a new mixer because Behringers are crap, I'd just like to mention that I never had this problem with my old Thinkpad T22 laptop with the same setup.

Anything anyone can suggest would be most helpful. I'm having serious issues ignoring this noise.

this seems to be a problem with dell notebooks. a solution that i was told by a friend is to use one of these:

http://www.radioshack.com/product/index ... age=search

it converts the three prong to two. i have tested this and it does work. i do not know why it works and i cannot tell you if it is a good or bad idea to do this but it definitely works.

Thats right!
i had the same problem with my laptop and skept told me to get one of these, and it worked!
i think its called ground loop isolation or something.

[thelibrarian]

Hum Eliminator by Ebtech. Nice device to have. Eliminates ground loop hum from everything from laptops to shitty PA's. I never play an event without one in my bag/car.

Best,
TL