Audio is stuttering since upgrade

[tuqqer]

Update: after hearing back from Plantronics, I decided it was time to do a clean install anyway (it'd been over 3 years). Sure enough, audio problem went away. Perhaps there'd been an easier fix, but there'd been some other really odd behavior happening, so I took this as the moment to get off my butt, put aside 4 hours on a Sunday, and zero the drive and reinstall everything one thing at a time. Mac is super fast once again. Thanks again for the suggestions.