Glitch when song has quiet section and comes in again

I have a couple of tracks which have a loud section which fades away, and then a vocal section starts. Before the vocal, there is a sort of bark/glitch of audio. It sounds something like an echo, but comes before the audio.

I have all my audio routed to a number of mixing groups, and then sends to two fx channels for pingpong delay and reverb. If I turn off both fx channels, the noise goes away. The noise is not there if I only play or export a short section of song, but If I play or export the part where the music fades out before the audio comes in, then I get the unwanted noise.

To remove the noise, I have automated both fx channels as shown in the image, and that gets rid of it, but I’d like to know what I’m doing to put it there in the first place, if anyone has any ideas?

The noise can be heard in the linked mp3 file.

http://www.climax.training/audio/extract.mp3

It sounds to me like a audio buffer of a voice track.

Since both fx channels are needed - the source is one track - not a plugin in fx channel.

To narrow down I would go like this:
Mute the tracks - one by one - that send to the fx channels(or any track).
That would identify which track that send this.
Then show all automation on that track.

Could be pre/post-fader send mixup or something that is not covered by automation as you think.

Are you automating bypass on any of your effects? Because on my setup this does a very strange thing when you un-bypass again in that it plays the last bit of audio that went into the plugin just before it was bypassed… which obviously results in a bit of nonsensical dislocated audio from ages back in the song.

Mike.

Thanks for the suggestions, it’s a bit clearer where it might be coming from, and I’ve managed to nail it on one track.

There is a 16 second gap in the audio, and just before the audio kicks in, comes the odd audio sound. The first insert effect is a gate to remove mic noise (hiss) in the quiet portion and I had a rather aggressive 11ms attack set on the gate. Changing to 100ms and tweaking a few of the other settings removes the noise. :smiley: