CPU maxing out and audio drop out while using VI

[zimmies]

I have a distinctive issue when using any VI within Pro Tools (all versions, 9, 10, 11 and now 12.82) even with only 1 VI (say mini Grand) and nothing else, when i play notes inevitably and repeatedly, my audio would cut off suddenly and then restore within 1 to 2 seconds which i believe also coincides with the master CPU meter showing 100% or close to 100% usage (in the red)
this on a 2011 iMac with a 4 core I7 processor through an UA Apollo 16. I have gone from Mountain Lion to Mavericks and now Sierra and still the same thing. All the UA drivers are up to date and it happens when i use a buffer from 32 all the way to 256 samples, above that i haven't really tried. This during live playing from an M-Audio Axiom 61 keyboard set on direct link.
nothing i have done (cleared out PT preferences) has done anything to alleviate this problem, does any one have any clues?
I cannot see how my OS, my PT software or the UA interface can suffer from this issue where no one else i know has ever experienced this issue. IS it possibly my iMac?
i am running 32GB of memory, before that i had 8GB and i also tried playing the CPU cores assignment, that did not work either

[albee1952]

Session on a separate/approved hard drive?

[musicman691]

Originally Posted by zimmies

I have a distinctive issue when using any VI within Pro Tools (all versions, 9, 10, 11 and now 12.82) even with only 1 VI (say mini Grand) and nothing else, when i play notes inevitably and repeatedly, my audio would cut off suddenly and then restore within 1 to 2 seconds which i believe also coincides with the master CPU meter showing 100% or close to 100% usage (in the red)
this on a 2011 iMac with a 4 core I7 processor through an UA Apollo 16. I have gone from Mountain Lion to Mavericks and now Sierra and still the same thing. All the UA drivers are up to date and it happens when i use a buffer from 32 all the way to 256 samples, above that i haven't really tried. This during live playing from an M-Audio Axiom 61 keyboard set on direct link.
nothing i have done (cleared out PT preferences) has done anything to alleviate this problem, does any one have any clues?
I cannot see how my OS, my PT software or the UA interface can suffer from this issue where no one else i know has ever experienced this issue. IS it possibly my iMac?
i am running 32GB of memory, before that i had 8GB and i also tried playing the CPU cores assignment, that did not work either

Could be your iMac. What do you have for a system drive? Please tell us it's not a Fusion drive as those are death to audio recording.

[Southsidemusic]

And do you have a fusion drive inside the iMac or a 7200 rpm spinner or an SSD?

Great minds think alike Jack We posted at the exact same time.

[musicman691]

Originally Posted by Southsidemusic

And do you have a fusion drive inside the iMac or a 7200 rpm spinner or an SSD?

Great minds think alike Jack We posted at the exact same time.

Crazy ain't it?