Re: why I cannot use C-Media USB Sound device when it's plugged on hub together with other devices?



张韡武 wrote:

I am pretty interested in this problem: if I wish to use this USB Sound
device on a hub which already have other USB devices plugged in, is it
possible? what should I do?

Does the hub in question have its own power supply? Does the USB sound device have its own power supply? If the answer to both of those is "No", then it's possible that the USB bus simply cannot supply enough power for the hub, the sound device, and the other devices. I forget how much power is available for so-called "bus powered" devices, but it isn't much. You might want to look up the specs for your devices to see how much they're trying to draw.
.



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