Hello Doug,
If you haven't already done so, please first:
- Exit Hauptwerk if it's running.
- Make sure you have the latest BIOS installed for the PC's motherboard. Check on its manufacturer's website for the latest version.
- Make sure you have all power-saving functions in the BIOS disabled, if relevant.
- Make sure all current operating system updates are installed on your new computer. (Use Windows Update to check for updates, apply all available, reboot, then keep repeating until there are no more. Note that you might need to click the 'check for updates' button *twice* before Windows actually performs the check.)
- Make sure that you have the latest versions of the drivers and firmware installed for all of your hardware, including any MIDI interface(s) and graphics card, checking on the manufacturers' websites.
- Download and install the driver for the Hauptwerk USB key, the current version of which is always available on our main downloads page here: http://www.downloadhauptwerk.com/ . (It doesn't hurt to re-install it if you aren't sure whether you already have the current version.)
- Disable all Windows power-saving functions, including the options for putting USB ports/devices to sleep. For example, on Windows 10 you would use 'Windows Control Panel | System | Power and sleep | Additional power settings', select the 'High performance' power plan, then click its 'Change plan settings | Change advanced power settings', then make sure that the settings are set as follows:
- Sleep: Hibernate after = Never (for 'plugged in' if present)
- USB settings: USB selective suspend setting = Disabled (for 'plugged in' if present)
- PCI Express: Link state power management = Off (for 'plugged in' if present)
- Processor power management: Minimum processor state = 100% (for 'plugged in' if present)
- Hard disk: Turn off hard disk after = Never (for 'plugged in' if present)
... then OK all of the screens.
- (Re-)install the latest version of MOTU's AVB driver/software: http://motu.com/download
- Make certain that you have the latest version of the MOTU 24Ao firmware installed.
- Reboot if you updated anything.
If that doesn't solve it, when the issue occurs, does using 'Engine | Restart audio/MIDI' make it produce sound again? (That menu option will stop, then re-start the, audio driver.)
Is the audio interface connected directly to a USB port on the PC, or via a USB hub?