[LAU] Awful noise out of FA-66

[Pieter Palmers]

Pieter Palmers wrote:
> Ken Restivo wrote:
>> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
>>
>> I plugged my spiffy new linux laptop into an amp tonight and used it
>> as an instrument with a band, using an M-Audio Axiom49 as a MIDI
>> controller.
>>
>> Not everything works yet on this new machine, but what I needed most
>> for tomorrow night's show (specimen, with a couple specialized
>> samples), worked fine.
>>
>> Except for the noise. The FA-66 was producing the most awful, buzzy,
>> glitchy digital background noise.
>>
>> I ran the following chain, and got horrible aliasing noise: Laptop ->
>>  ExpressCard Firewire -> FA-66 -> SWR bass/keyboard amp
>>
>> The FA-66 is powered by its wall-wart, since the ExpressCard doesn't
>> power it (even though it is a 6-pin connector).
>>
>> My question is this. What's up with that awful noise?
> 
> When googling around I found at least one other person having the same 
> issue with the FA-66.
> 
> I've noticed similar noise at some places with my QuataFire line out's.
> 
> Some things to try:
> - unplug the power supply of the laptop (for test)
> - put a DI box inbetween the amp and the edirol (enable ground lift)
> - use another power supply for the edirol (preferably a transformer 
> based one).
> 
http://docs.info.apple.com/article.html?artnum=86655

Pieter