Bug - transition timelines and fade-outs on end of "to be played" audio clip

This is just a bug report (or else I’m making a mistake I don’t understand), I wasn’t sure where to put it.

In this example, I have a transition timeline triggered by a parameter called MusicPosition. In this very specific case, I had no sound coming from the Frozen River track when the transition was triggered at the end of the loop : the second clip just stopped, whereas the first clip had to play since the playback was going back to the start of the loop as “Source” in the transition timeline. After investigating further, it seemed that removing the fade-out from the end of the first clip played in this loop by the Frozen River track solved the issue. I don’t think this is meant to happen.

Have a great day !

I’m afraid I don’t totally understand your description of what happened. However, since you mentioned fade curves, I may have an idea as to to the cause.

Fade curves on the timeline are effectively a kind of volume automation. Thus, when the playback position jumps from a point to the right of a fade-in or fade-out curve to a point to the left of the curve (or vice versa), it’s jumping from a location where the volume is automated to -oo dB to a point where it is automated to 0 dB (or vice versa). This results in the volume suddenly dropping to silence or suddenly rising from silence to full, which can be surprising if you don’t expect it.

If that doesn’t explain the behavior you observed, could you please explain in more detail exactly how the behavior you observed differed from what you expected?

Can you demo your problem? I’m not able to reproduce it (the “source” plays the beginning of the loop correctly). Which version of fmod are you using?

Hi !
What I am expecting in this situation :

  • The sources (the Frozen River and Frozen River Mel tracks) play accordingly to the way I set them up in the transition timeline, even if it means that when specifically triggering a transition timeline at the end of the loop the source consists of audio clips playing at the beginning of the loop.

What is happening :

  • When the audioclips from the beginning of the loop are triggered (because they are visually triggered - just check the luminosity of the mentioned clips when the transition timeline triggers), both the sources (Frozen River and Frozen River Mel) remain silent when playing the transition timeline.

I am not sure I managed to explain things clearly, so just compare what happens when I remove the fadeouts curves at the end of the two clips.

By the way I am using FMOD 2.01.11.

Thanks !


1 Like

Thanks for the clarification. That video helped a lot.

Having investigated a little deeper, it appears that this is actually a previously-undiscovered bug in how transition timelines interact with the fade curves of instruments on the main timeline. Thank you for bringing this issue to our attention; I’ve added it to our bug tracker to ensure that it is fixed in an upcoming version.

In the mean time, you should be able to work around this issue by baking your fade-ins and fade-outs into your source audio files instead of creating fade curves in FMOD Studio, if you believe those fade curves are likely to take place during a transition timeline.

1 Like

Thanks ! I am so proud that I discovered an actual bug instead of using FMOD incorrectly :smiley:

Have a great day !

1 Like