Dear All, We develop a USB Device includes 3 interfaces (Speaker, Microphone and HID) We also develop an API to use several of this one, for that, I have to be able , in the same time, to differientiate several devices plugged into the PC and to link the Audio Interfaces corresponding with the correct HID interface for each device. I though to use the serial Number to differientiate these one. For HID interface it is easy to get it . But not for the Audio interface, it seems more complicate Could you explain me the method ? Or have you got another method to differientiate and to link ? Thanks in advance Raphael ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/ ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/