paulkinzelman wrote:When you say "selecting WAV input", I assume you mean Audacity | Edit | Preferences | Input?
No, I mean in the Realtek mixer/control panel. Set Audacity to "MME: Realtek HD Audio Input".
paulkinzelman wrote:When I set it to the 1st (M$ Sount Mapper), I get some weird echo effect, completely unusable.
You've got a feed-back loop going on.
Make sure that "software playthrough" is disabled in "Edit > Preferences > Audio I/O". Set Audacity recording input to "MME: Realtek HD Audio Input" (on the same Preferences page), then over to the Realtek GUI (the mixer/control panel thing). When using the loop-back connector, the Realtek GUI should have only the "Line input" selected.
Before you change anything though, let's go back to the beginning. (please read this entire post as there are several possibilities as to what is going on)
You are wanting to record the audio from a YouTube video that is playing on your computer.
Without the loop-back connector, you can hear the video from your headphones/speakers.
With the loop-back connector, the sound is coming out from the soundcard, going into Audacity, then back out of the soundcard again, into Audacity, and round and round, making a weird echo.
One explanation is that you have "software playthrough"
enabled (Audacity, through software, "echos" the input to the output.
The second explanation is that you have "software playthrough"
disabled, but the Realtek driver is routing the line input to the line output. To check if this is the case, plug your loopback connector into the Line input only. Open Audacity and click on the recording meter. Now touch the tip of the free end of the loop-back connector and you should see the input meter in Audacity flicker (picking up mains hum) as you touch the tip of the plug. If you turn on your speakers (with them connected to the soundcard output, do you hear the hum? If you do, then the input is clearly being echoed to the output.
You have checked that "software playthrough" is disabled, so you know that it is not Audacity that is sending the signal back out. Go to the Realtek GUI and look at the "playback" page and mute the Line input for
playback. (If your Realtek mixer looks like this
http://img141.imageshack.us/img141/6280 ... xer0wi.jpg then note the arrows on the right hand side that allow you to scroll left and right to see the other outputs - alternatively, it may be on the Audio I/O page of the Realtek GUI). You should still see the recording meter in Audacity flicker when you touch the jack, but not hear it. Your loopback connector should now work.
paulkinzelman wrote:But when I record with Audacity, when I have it set to the 2nd input (Realtek) I get garbage when I listen to what Audacity recorded when something is playing.
Is this different to the "echo" that you get when you select "Microsoft Sound Mapper"? More like a reverberant distortion than an echo? It's possible that you have accidentally set things up to record "What U Hear" (Stereo Mix) - which is what you wanted in the first place. With "Stereo Mix" selected as the recording input, the soundcard will record from the signal as it appears at the output jack. In this scenario, you will be recording both the Line input, and the direct output from the video at the same time (also if the output (playback) from the Line in is not muted (as above), then you will be recording that as well). The result will be a mess. The solution, if this is the case, is just to remove the loop-back connector.
