Can't get rid of Audio "Ghost" when bouncing to tracks

[Michael McBroom]

I'm working on a piece that, at the moment, is 100% MIDI. Earlier, however, I recorded an audio track of guitar. But I wanted to keep this file clean of audio, so I renamed the file with the audio, then I deleted the audio track and saved it to its original name.

When I bounce to tracks so I have an audio copy of the song, there is at the end a leftover sound from the audio track. Immediately after completing the bounce, this sound, well it's a chord, actually, continues until I stop the playback. But it is only recorded up until the end of the piece. That in itself is strange. It reminds me of when a MIDI instrument will sometimes get stuck on a note or a chord, but this is audio. This sound is only audible after I've bounced to a new track.  When I play the song back, there is no trace of this leftover audio, and there shouldn't be either since there are no audio tracks anymore.

To attempt to rectify this, I exited the file, and called it up fresh from memory, then did the bounce to tracks again. Same thing, the audio "ghost" is still there. Taking a look at the bounce options, I decided to try setting the Source from "Entire Mix" to "Tracks," reasoning that, since only MIDI tracks are present, it couldn't pick up any leftover audio. But it still does.  Next, I tried different driver modes. Normally I use ASIO, but I switched to WASAPI Exclusive. Same result. Then I tried WDM/KS. Again, same result. I didn't bother with any of the others, figuring I'd get the same result.

Well, I'm stumped. I don't know what else to try -- and I don't have a clue as to what is causing this. One thing I just thought of. What if I record an empty audio track to this file. Would that possible overwrite whatever has gotten stuck in the works somewhere? I'm gonna give that a try and I'll report back.

Welp, that didn't work either. So I just recorded an empty audio track, saved the file, then tried bouncing to tracks, but this time I selected "Entire Mix." Reason why was because when I selected "Tracks," the Bounce routine created two tracks -- one a recording of the MIDI and the other a recording of the blank audio track. I didn't want that, so I went with Entire Mix instead.

 

 

Edited February 2, 2020 by Michael McBroom

[57Gregy]

I would check for any tracks you might have hidden and forgot about. That audio may be there.
Next, if the original audio track the guitar was in is still in the project, I would set it's output to 'None' or mute the track. 
You must be using some soft synths if you want an audio mixdown. Set those synth outputs to a bus (Master) and select Buses for the Source and Master (or whatever you named the bus) making sure the errant audio track isn't also set to that bus.
Good luck!

[scook]

8 minutes ago, 57Gregy said:

Next, if the original audio track the guitar was in is still in the project, I would set it's output to 'None' or mute the track.

Better still, archive the track. Audio tracks that are muted or routed nowhere still must stream their clips from disk into memory. Archived tracks take no resources at all except for the space they consume on disk.

[Michael McBroom]

That's just it, though. I deleted the audio track -- or at least I thought I did. It doesn't exist anymore, far as I know. It certainly doesn't appear anywhere. I've never hidden a track before -- I'd have to consult the CW online Help just to find out how to do that.

Frustrated over this whole business, I learned a lesson. I should have saved the file before I recorded the audio. But I didn't. And in fact, I'd done a lot of work on the project before recording the guitar part, to make things worse. I ended up having to rebuild the entire piece. Fortunately I had clean components of it that I was able to reassemble, but it was still a time consuming process. Took me all afternoon yesterday getting the project back to where it was before I made the recording. Lesson learned.

I'm still baffled and really curious as to why this happened, though. Hopefully it doesn't repeat itself.

 

 

[Kalle Rantaaho]

What a strange issue, really!

What turns your MIDI audible? Are you using simple instrument tracks or separate MIDI/audio output tracks?  If you're using external synths, it's another story, but the audio output tracks for soft synths (also the hidden one in a simple instrument track)  are audio tracks as much as any.

I don't know if it's even theoretically possible, but could the ghost audio lie at the end of a soft synths audio output track? So it would only play back when bounce function is used and the MIDI-signal has stopped?  If you're using simple instrument tracks, could changing them to  "traditional" pairs reveal the hidden audio waveform on one of the audio tracks??

If , for some reason, you're using the motherboards wavetable synth, I don't know what to say.
 

[Michael McBroom]

Nope, I'm using CW's TTS-1 for GM, and just its default setup protocols. The audio trace is there before I do any bounce to combine tracks. And yes, since it's actually a chord that's bleeding through, I suspected it might be a MIDI track, so I checked the most likely culprits -- MIDI guitar and keyboard tracks. Nope, nothing there. It was definitely in the audio.

I ran into this again with the same piece of music, but in a different spot with a different guitar. This guitar is a Gibson with P90 single coil pickups that can be rather noisy. There's a four bar intro to the piece, before the guitar part starts and, during playback, I couldn't help but hear a rather pronounced bit of line noise in the guitar's audio track while I waited for the Intro to complete. So I highlighted the noisy "dead" area before the guitar started, then I used the Edit>Cut command to remove the snipit from existence -- or so I thought. Now, the way it sits, the audio channel has no signal from the beginning of the tune to the end of the fourth measure, but if I solo that track, I still hear those four measures of line noise. Strange, eh?

I got to thinking that it may actually be the Auto Save function causing this, since a save was done right before I deleted that section, and I was wondering if that, somehow, was messing with things. So I deleted the Auto Save file and tried again. Nope, line noise is still there. Not a huge issue, but an annoying one. I used the "Write" function to reduce the audio track's volume to "0" prior to the start of the 5th measure.

 

Edited February 4, 2020 by Michael McBroom