Playback Inaccurateness in PT10

[Jakub]

Hallo,

I've observed this problem on three systems already, each with different sound card, the only common specification being PT version 10.2 on Mac OS X (both Snow Leopard & Lion). I would be very happy if someone would take one minute to test if this is a software based problem or maybe a configuration issue of mine:

Steps to reproduce:

1. New Session
2. New Audio Track (mono / stereo)
3. Create a Region with Signal Generator (AudioSuite > Other) test tone (any lenght, any signal type at any level) somewhere on the track, e.g. at 1:00 (not at the beginning please)
4. Select the region with the tone (if it isn't selected already) and issue the Play by pre-roll value up to selection start shortcut Option+Left Arrow

On the systems I work with, Pro Tools auditions also a small part (about 450 samples) of the following selected signal which logically shouldn't happen.

Some related observations:

• This is the case with ANY audio signal, the Signal Generator being just an example here. And it ins't limited just to region boudaries of course.
• If you select a silent part just before the test signal region and play it (Space bar or Opt+[) Pro Tools also plays a little after the selection. If you delete the audio signal following immediately after the selection end, the problem disappears.

Please, if there is someone having one or two minutes of free time, would you be so kind and make a short test, if your systems indicates similar behaviour? Do you have any idea what am I doing wrong?

Thank you all in advance,


Jakub

[Basstian]

Did you engage the automatic cross fade option in the operation preference pane?

[Jakub]

No, there is no such option in my PT.

The problem is I use the "Play by pre-roll value up to selection start" feature very often when editing and it's quite funny when you position the editing cursor right before a transient, press "play before cursor", and you hear the transient.

I thought that the waveforms could be shifted in some way, however if I try to follow the transient with the scrubbing feature, it's audible on the right place where it is actually displayed.

Could anyone please try this on his/her system?

Thank you very much!

[Basstian]

It is probably a problem with the delay compensation.

Did you try to turn it off?

[Jakub]

Yes I tried, also setting various buffer sizes and no change. Anyway, the problem seems to occur regardles of plug-in usage.