Pro Tools DAE Error -9171 and other CPU Overload errors at low buffer sizes
When using Pro Tools 10.2 on a Mac or Windows dual-processor system and Host Processors in the playback engine is set to a number of cores that is equal to double the number of physical CPU cores, playback at the lowest available buffer sizes will yield CPU Overload errors.
For example, if you have a dual 6-core CPU with Hyperthreading enabled, Pro Tools will allow 24 Host Processors to be used.
If you are using 32, 64, 128, or 256 sample H/W buffer sizes on a dual-processor system, set Host Processors to the number of actual physical cores.
In the dual 6-core CPU example, the desired Host Processor setting to avoid errors strictly related to this bug would be 12.
This bug does not occur at H/W buffer sizes above 256, but is seen most frequently at 32 and 62 sample buffer sizes. This bug is not known to occur on single CPU configurations.
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