Classification: UNCLASSIFIED Caveats: NONE Hi Rahul, First of all - USB based sound cards are notoriously terrible for temporal accuracy. Your best bet really is to get an PCMCIA-based card. The reason is, the data bus of the USB is not all that fast - it's high bandwidth, but has a slow sample rate - default is only 125 Hz. This means you can only "deliver" a sound to begin roughly every 7.5 ms... So if the sound delivery from the hsystem does not line up appropriately, you will have a gap while it "waits" to sync w/ the USB data bus. Now there is hope! In Windows, you CAN change the USB sample rate, using an applet. This one here will do it: http://www.softpedia.com/get/Tweak/System-Tweak/USB-Mouserate-switcher.shtml It allows changing the data rate up to 1000 Hz (1 ms resolution). Note - this changes the access rate for ALL USB devices; mice, remote drives, access keys, etc. It may also decrease the time you get out of the battery, due to larger power consumption. IMO, spend the $$ on a good PCMCIA card and be done with it. Good luck, Dave ------------------------------- Dr. W. David Hairston Research Fellow Oak Ridge Affiliated Universities Auditory Research Team, VAP, HRED Army Research Lab Aberdeen Proving Ground, MD 21005 Office: (410) 278-5925 Fax: (410) 278-3587 -----Original Message----- From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxxxxxxxxx] On Behalf Of Shrivastav,Rahul Sent: Friday, August 08, 2008 2:22 PM To: AUDITORY@xxxxxxxxxxxxxxx Subject: [AUDITORY] Sound card problems Folks - I wonder if someone on this list can help us with a problem we are having with our sound card: We purchased a Creative E-MU 0202 USB sound card to use with a laptop. Unfortunately, when we play wav files through this sound card, they occasionally skip for a few milliseconds. The skipping occurs at random intervals and does not seem related to the file size. The problem does not occur if we play the same sound file through the internal soundcard on the same laptop. We have already done most of the usual troubleshooting steps - update/reinstall drivers, used both USB 1 and USB 2 ports, etc. - but none seem to have worked. Has anyone observed such a problem before? Any solutions that you can suggest? Also, do you have another "favorite" amongst external sound cards? We want to use it to run some speech tests in the field. Thanks for all your help! Rahul ----------------------- Rahul Shrivastav, Ph.D. Associate Professor Dept. of Communication Sciences and Disorders Dauer Hall, PO Box 117420 University of Florida Gainesville, FL 32611 Phone: ++-1-(352)-392-2113 (ext. 230) Fax: ++-1-(352)-846-0243 ----------------------- Classification: UNCLASSIFIED Caveats: NONE
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