Let me first describe the situation I am dealing with. I am an amateur musician playing an old Casio CTK-591 keyboard with a single headphones output. I use that output to connect it with my computer with a jack cable (as the line-in). To the other socket in my PC I plug in a simple VOIP microphone. The last computer socket that I use is output for headphones, so I could here my keyboard while recording.
Previously I used Windows XP and I had no problem with recording both the keyboard and my singing voice. I only ticked off both the devices I wanted to record (mic and line-in) and I could independently set up their volume level and recording sound level. Usually I muted the mic so I didn’t hear it while recording, because hearing my echoing voice in the headphones was really distracting and annoying. So I was only listening to my keyboard in the headphones and I was very happy with that solution.
But here came Windows 8.1 and ruined everything I had Now I can freely select the audio devices I want to record. I have to go to the control panel and select the option of “listening to the device” in the microphone field. The funny thing is I don’t have to do so in case of the line-in socket because for some reason the keyboard is being listened to all the time although the "listen to " field is not ticked off o.O Anyways, and now I record them both by recording the “Mix Stereo” device, but that’s a huge problem… Because I can’t mute my mic so I didn’t hear it now. There’s no use in muting it with the microphone equalizer in Realtek settings, because Mix Stereo hears it anyway and it is the mix stereo output what I hear. So this is my question. Is it somehow possible to record both line-in and mic but hear only line-in as the output?