Glad to hear you had no difficulty connecting your SoundLink Micro to your Windows PC for audio! In regard to using the speaker as a microphone, have you checked your PC audio settings, to see if the speaker is listed and selected as the microphone, rather than something else? Also, have you tried using this speaker's microphone with another device to test?
What you may want to try is a reboot on your computer and also reset the speaker by holding the power button for ten seconds, then attempting to re-connect the speaker. Let me know if you notice any improvement!
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