LAPTOP N SOUNCARD=BUZZING?!?!?

[bishtay elliott]

i have a laptop linked to a M-audio 410 firewire soundcard---------all is good runs like a dream--however tried it on a really loud system and could hear a buzzing noise- quite loudly!! evn when the outputs on the (pa) mixer were muted?!? also when i touch the built in mouse i get a change in the buzzing??!?!?
any ideas my friends? :doh:

[gumpy green]

its prob the noise on the power supply.

check if it does it runnin on battery.

[bishtay elliott]

will do mate!

[schlongfingers]

If this is as a result of the power supply being plugged in (which I'd bet my right hand on) there are a few ways round this:

a) get a ground loop isolator - http://www.maplin.co.uk/Module.aspx?ModuleNo=33172&&source=14&doy=search

b) remove the top pin from your power supply, if you don't want to mess around with your power supply buy a three point blosk splitter and remove the top pin from that - this of course is slightly dangerous, but you're unlikely to get a serious shock from a laptop

c) plug your laptop power supply into a different elkectrical loop if you are lucky enought to have one close to hand - In my living room one wall is on a different loop to the other, so long as I plug my laptop into the socket on the other side of the room to my decks/amp etc i get no noise issues :D was well chuffed when i found this out.

[schlongfingers]

If this is as a result of the power supply being plugged in (which I'd bet my right hand on) there are a few ways round this:

a) get a ground loop isolator - http://www.maplin.co.uk/Module.aspx?ModuleNo=33172&&source=14&doy=search

b) remove the top pin from your power supply, if you don't want to mess around with your power supply buy a three point block splitter and remove the top pin from that - this of course is slightly dangerous, but you're unlikely to get a serious shock from a laptop

c) plug your laptop power supply into a different elkectrical loop if you are lucky enought to have one close to hand - In my living room one wall is on a different loop to the other, so long as I plug my laptop into the socket on the other side of the room to my decks/amp etc i get no noise issues :D was well chuffed when i found this out.

[dan the acid man]

please dont do b, as pc power supplies and laptop power supplies store electricity, so i wouldnt go messing around with them

[TechMouse]

A ground loop isolator costs about £4 from Maplin, so I'd go with that.

[bishtay elliott]

reeeeeeeeeeeeeeeeeeespect!
:love: :love: :love:

[gumpy green]

please dont do b, as pc power supplies and laptop power supplies store electricity, so i wouldnt go messing around with them

would this work anyway.

my laptop psu is double insulated-----only has Live and Neutral so i dont think ther is an earth connected to mine.

neva treid it on a pa but in the bedroom i dont notice any humming.

manybe sony have did this for me....

but-

ground loop isolator defo would be the best.

[schlongfingers]

I never tried a), but for 4 quid i think it's worth a blast

b) and c) worked for me, but have removed my modified socket block now :D

[tocsin]

Yeah, def sounds like a groundloop issue. Unfortunately, the groundloop isolators have never worked for me. The best way I found to get rid of it is to buy an adaptor that removes the grounding. If you don't get hit by lightning, you should be fine.

[pumpinglemma]

I had this exact problem with the same hardware. Laptop + m-audio
firewire 410. I did ( b.)
I cut the the wires from the earth pin - central pin and voila noise is
gone.
Apparently laptops are low power so u wont fry yourself or the hardware
if u try it. I was humming and hawing(no pun ;) about this for months
before I did it, for the exact reason of not being crazy about frying
myself or laptop but it works and I've loads of plugs plugged into the
same board.
I didnt go for a ground loop because the ground loops on offer only
come with rca i/o while the 410 has 1/4 inch jacks, which are better. It
meant more cables also and I've enough already all over the place!
Go for option (b.) I reckon.