audio distortion with usb headphones at DVinfo.net

Peter Schmitz · September 26th, 2005, 12:03 AM

I use a PlantronicsDSP500 usb-headphone, which in general is very good and pleasant to work with.

But now I hear after a few seconds crackles that will end in a very noisy distortion of the sound. It sembles a static kind of noise.

What could be the reason for this ?

It appears in Final cut pro, but also in Peak.

Douglas Spotted Eagle · September 26th, 2005, 07:13 AM

Aside from the fact that it's USB? Given that it's Plantronics, it could be something to do with an electret element, or piezo element, or that your system is stumbling with resources in the process of recording the mic or converting it back to analog. (When you use a USB mic and monitor it, it's an analog to digital to analog conversion, and you're already starting out with what is likely a compromised signal)
Try defragging, first, would be my recommendation.

A. J. deLange · September 26th, 2005, 02:48 PM

Does the crackling appear on the recording? If not then it is probably the USB driver for the headphones being unable to keep up with USB traffic (including the mic in) and headphones out. If it does appear on the recording as well it may still be the same thing but would be nice if the software protected the incoming path at the expense of monitoring.

In either case you may want to try putting the mic and headphones on different USB busses. Also get rid of any hubs you may have in the system.

Peter Schmitz · September 30th, 2005, 03:07 AM

A. J. deLange: I think u are right. I use a hub (not for the plantronics btw) and it occurrs when other jobs were running.

I also thought it could be caused by Coreaudio?? Because I always have trouble with peak and Coreaudio ('cannot find Coreaudio', it says when starting up).

Anyway, right now the Plantronics is working fine again.

Kind regards,

Peter Schmitz

September 26th, 2005, 12:03 AM	#1
Peter Schmitz New Boot Join Date: Feb 2005 Location: near Arnhem (Netherlands) Posts: 10	audio distortion with usb headphones I use a PlantronicsDSP500 usb-headphone, which in general is very good and pleasant to work with. But now I hear after a few seconds crackles that will end in a very noisy distortion of the sound. It sembles a static kind of noise. What could be the reason for this ? It appears in Final cut pro, but also in Peak. __________________ Peter Schmitz writer-producer-director documentaries and arty videoclips

September 26th, 2005, 07:13 AM	#2
Douglas Spotted Eagle VASST Join Date: Jan 2004 Location: Stockton, UT Posts: 5,648	Aside from the fact that it's USB? Given that it's Plantronics, it could be something to do with an electret element, or piezo element, or that your system is stumbling with resources in the process of recording the mic or converting it back to analog. (When you use a USB mic and monitor it, it's an analog to digital to analog conversion, and you're already starting out with what is likely a compromised signal) Try defragging, first, would be my recommendation. __________________ Douglas Spotted Eagle/Spot Author, producer, composer Certified Sony Vegas Trainer http://www.vasst.com

September 30th, 2005, 03:07 AM	#4
Peter Schmitz New Boot Join Date: Feb 2005 Location: near Arnhem (Netherlands) Posts: 10	Thx for all the advice A. J. deLange: I think u are right. I use a hub (not for the plantronics btw) and it occurrs when other jobs were running. I also thought it could be caused by Coreaudio?? Because I always have trouble with peak and Coreaudio ('cannot find Coreaudio', it says when starting up). Anyway, right now the Plantronics is working fine again. Kind regards, Peter Schmitz __________________ Peter Schmitz writer-producer-director documentaries and arty videoclips

September 26th, 2005, 02:48 PM	#3
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	Does the crackling appear on the recording? If not then it is probably the USB driver for the headphones being unable to keep up with USB traffic (including the mic in) and headphones out. If it does appear on the recording as well it may still be the same thing but would be nice if the software protected the incoming path at the expense of monitoring. In either case you may want to try putting the mic and headphones on different USB busses. Also get rid of any hubs you may have in the system.