How to Change the Sound Card Buffer Size

Download the ASIO4ALL utility program (See Resources). Install the utility by double-clicking the downloaded file and follow the installation wizard prompts.

Browse the Start menu to find the ASIO4ALL program group and click ASIO4ALL icon to start the utility. You'll be shown the WDM Device List. Find your sound card and click it to select it.

Slide the ASIO Buffer Size slider to the right to lengthen the buffer size. Play audio to test whether the audio has stopped underunning and glitching. If it has not, continue making adjustments to the buffer size in ASIO4ALL.

Click the "Wrench Icon" at the lower right to open advanced settings. Here you can make further adjustments. The most useful for fixing underrun errors is the "Use Hardware Buffer" box. Check this box to use your sound card's hardware buffer, if applicable. Whether this setting makes a difference depends on your sound card's design and installed drivers.

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