J
jvl642
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We are developing a 4-channel, 48K UADC2.0 compliant USB audio interface. It enumerates and streams (for a while) but the host driver (usbaudio2.sys) never issues IN tokens for feedback despite the fact that we have a properly defined feedback endpoint and our OUT endpoint is configured for isochronous, asynchronous data operation. We can capture the complete enumeration process including the host querying the fixed sample rate of 48K. When we select our device as the speaker output the driver starts streaming to the OUT endpoint (using the first 2 channels as 24-bit speaker output and placing silence in the other 2 channels) but it never issues a single IN token to the same endpoint number as the OUT endpoint number to read the 4-byte feedback value.
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