Help! Some effects plugins creating silence

I have a stereo audio file and I am trying to effect it with various pluggins like transient mangler, dj flanger, gverb and many others. When I apply the effect to the whole file it only works on part of the file and the rest is silent. If I select the part that becomes silent before applying the effect everything is silent. Even though it is silent there is a blue bar as if there was a constant wave form of low volume there. I edited the envelopes of the waveform so that might have something to do with it, but I tried to set them back to normal.The effects will apply correctly to all other files and many other effects still work perfectly on the file that I edited the envelope points in, but a few will not. I am on os x.

Thanks for any help.

Which version of Audacity are you using? Modern Macs do not support Audacity 1.2.


I’m on 1.3.12

Here’s a picture. As you can see part of the effect worked, but the rest is the blue bar. It doesn’t matter if I use the multi-tool or the selection cursor.

Which effects are causing this problem?