With GFX and LFX APOs, even if you didn't provide a property page, the APO could be bypassed using the "Enable Audio Enhancements" checkbox in the Microphone Properties dialog. I've now changed one of my LFX APOs into an EFX APO for Windows 8.1. It appears that the APO can no longer be controlled by the "Enable Audio Enhancements" checkbox -- the APO is always being called. Is that the expected behavior? Is there no longer a global "disable"? -- Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc. ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/