[Avid]

There is a condition in Pro Tools 5.1 that can cause "garbage audio". Garbage audio can manifest as noise or audio from random areas on the record drive. This can occur when performing open ended record passes or record passes with large boundaries when there is a large interval between the session start time and record start time. This issue will be fixed in the next free maintenance release of Pro Tools.

The specific condition that triggers this problem is if the number of minutes from session start to record start plus the number of minutes of audio that can be allocated for record is greater than the maximum session length.

At 44.1 kHz:

* Garbage audio is created if (record start - session start) + minutes that can be allocated > 9 hours. "Minutes that can be allocated" is set in preferences.
* Open ended record allocates up to 270 minutes.
* Max session length is 811 minutes.

At 48 kHz:

* Garbage audio is created if (record start - session start) + minutes that can be allocated > 8 hours. "Minutes that can be allocated" is set in preferences.
* Open ended record allocates up to 250 minutes.
* Max session length is 745 minutes.

Example of problem at 44.1 kHz: With open ended recording and a session start time of 1:00:00, (60 minutes) bad data will be recorded if the record start point is past 10:05:00 (605 minutes). i.e. (605 - 60) + 270 is greater than 811.

Workarounds:

1 - Reduce length of time between start of session and record start point to be less than 9 hours at 44.1kHz or 8 hours at 48 kHz.

2 - If the amount of time between the session start and the record in point is greater than 9 hours at 44.1kHz or 8 hours at 48 kHz, open ended record should not be performed and the record length should be bounded by creating a selection not exceeding the following guidelines:

* At 44.1 kHz: (13 hours 31 minutes - [Record Start Time-Session Start Time]) minutes.
* At 48 kHz: (12 hours 25 minutes - [Record Start Time-Session Start Time]) minutes.

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Digidesign Technical Support