II have Windows 7. I have used Audacity for many years. Suddenly I cannot record. I can listen. When I hit Record all I get is a flat line and there is no sound on Playback. Something must be going in because the red/green bars at the top show it, but there is no wave form. I have download the program twice, but I get the same result. Before if I re-installed, it worked perfectly as soon as I turned the program on. I must be doing something wrong, but I have tried everything I can think of. I use it frequently and I hope someone can help me!