PCM2702 on / off noise

I'm building a USB soundcard with a PCM2702. I have built the thing on a breadbord to test it. It sounds pretty good, but when I unplug the USB connector from my laptop or when I turn off my computer I hear a very anoying noise.

This is very anoying because I have my headphones on when I turn off my laptop.

How can I get rid of this noise?

Do you have any other advise for my project?


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I placed a 100uF capacitor between Vbus and GND. With the USB output resistance, it functions as a low pass filter.

The off noise is fully eliminated, but there is still a small on noise. I think the on noise is now produced by the charging of the 100uF capacitor. I will try a smaller capacitor.

I will also try a coil in the Vbus line. That functions as a low pass filter too, but maybe it works better.