I upgraded to 10.5.7. All good but with GoToMeeting v4.1. When I use my Logitech Headset A-0356A, people sound like chipmunks. Without headset they sound OK. Sound through headset OK with Skype and with iTunes. Checked headset with GoToMeeting on another computer with OS X 10.5.6 and they were OK. Spent time with Citrix Help Desk (they make GoToMeeting). Ran test. Reinstalled App. Rebooted from Safe Mode and repaired permissions. No go. Contacted Logitech Support - they blew me off. Anyone experienced this or have any suggestions (other than go back to 10.5.6). Thanks.