If you are installing Cakewalk Audio Pro v.9.0 after v.8.0, we recommend removing 8.0 first rather than installing 9.0 over it. In our internal testing, installing 9.0 over 8.0 resulted in a maximum audio track count of 2 (!). If we uninstalled 8.0 before installing 9.0, we could play as many as 8 24-bit tracks. We do not know the cause of this difference in performance but we do know that uninstalling 8.0 first fixed it. In Cakewalk Pro Audio v. 9.0:1) Go to Options | Audio and select the Drivers tab. 2) "Digidesign d24/Mix: Chan 1 - 2" should be enabled for both input and output drivers. 3) Select the General tab. 4) "Digidesign d24/Mix: Chan 1 - 2" should be enabled for Playback and Record Timing Masters.5) You will have to experiment with " [Number of] Buffers in Playback Queue" and "Buffer Size" to find the best setting for your system configuration. 6) Select the Advanced tab. 7) "Simultaneous Record/Playback"should be checked. 8) "Stop On Driver Underrun" should probably be checked. See Cakewalk help for more details.9) "WavePipe(tm) Acceleration" should NOT be checked. Cakewalk's WavePipe technology is not compatible with the d24/Mix driver.10) "Unpack > 16 bit audio" should NOT be checked. 11) "Left-justify unpacked data" should NOT be checked.12) Select the Device Profiles tab and select the "Digidesign d24/Mix: Chan 1 - 2" profile.13) "Use Wave Out Position for Timing" should be checked.14) Press OK to close the dialog and save your settings.