Re: Native mode IO problems
Re: Native mode IO problems
- Subject: Re: Native mode IO problems
- From: "Stephen F. Booth" <email@hidden>
- Date: Wed, 3 Feb 2010 23:43:14 -0800
>> I have a MacBookPro4,1 and as it turns out the USB ports are not equal. I
>> had the Benchmark DAC plugged directly into the laptop using the port on the
>> left side, and the Wavelength DAC plugged into the keyboard which was
>> plugged into the port on the right side of the laptop. For reasons that I
>> can't explain, if I swap the DACs the problem swaps also. If I plug both
>> DACs into the port on the right side then everything works properly for
>> both.
>
>
> The MacBookPro4,1 is a 17-inch model with *two* USB ports on the left and
> one on the right. Others have reported that the left USB port closest to
> the power supply jack is less reliable for audio, presumably because of poor
> isolation from the power supply jack. The other USB port on the left
> reputedly is much better.
Actually my MacBookPro4,1 is a 15" model- since it is the 15" model it
only has two USB ports, one on the left by the power connector and one
on the right by the FireWire port.
I've done a bit of experimentation and only managed to confuse myself,
because the problem appears to be related to USB power. Both DACs
glitch when plugged directly into either of the laptop ports while
sending 24-bit integer audio (device native format). However, both
DACs work just fine when plugged directly into either port sending
32-bit floats.
I also tried a Belkin 7-port powered USB hub and both DACs work fine
when connected at the hub sending both 24-bit ints and 32-bit floats.
I also can plug both DACs into my monitor (a cinema display) and get
proper results.
I'll be the first to admit that this sounds extremely bizarre, but it
sounds like I'm not the first person in history to have issues like
this.
Stephen
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden