7.4 becomes unresponsive

[Ed Douglas]

G' Day.
I just bought an MBox micro and installed it on my dual 1.8GHz G4 quicksilver (1GB RAM, OSX 10.9). Previously I was running OSX 10.11 and PTLE 7.3.1cs5 with an MBox 1 without a hitch. Now, under 7.4, even a small session hangs after a few mins of playback, looping a short section of audio endlessly. After a few seconds, I do regain use of the cursor and can place it anywhere on the timeline but Protools will no longer resume playback.

I have tried everything suggested here, Re-installed the OS and brought it up to 10.9, deleted all prefs and database files, checked permissions, removed all plug ins, but to no avail. The problem persists even if I substitute my original MBox for the micro. My laptop config (1GHz g4 powerbook, 2GB RAM, OSX 10.11 PTLE 7.4) runs fine under both sets of hardware, and again I did not have these issues on the tower with 7.3.1cs5.

my playback engine settings are as follows:
Buffer - 1024
RTAS Proc - 2
CPU Limit - 90%
• ignore errors during playback

DAE Buffer 1500ms (level 2)
Cache - Normal

Any ideas?

TIA

[Slim Shady]

How did you get a dual 1.8ghz G4 Quicksilver? I assume there's some sort of upgraded CPU card in there, and that may be what's causing your problems. Note that Quicksilver models are not qualified for use with 7.4 and fall under the "not recommended" category here.