Not exactly sure if audio interface means external hardware. If so, I'm not using any. Just trying to mix pre-recorded wav tracks. Yes to ASIO. I'll look into WASAPI shared, not sure without researching it what that is. I haven't done any of this for over a decade so a little rusty on terms.
I don't think Windows Media Player is the problem for either of my issues (inability to play project or the extra bass in export). After rebooting and creating a new project it too will no longer play once i saved it, closed CW and re-opened it. WMP wasn't used at all that time. And after getting frustrated with this last night I downloaded trial version of Reaper and re-mixed it all there. Reaper's export did not sound any bassier than expected.
The bass thing though isn't as big of a deal as the not playing project. Hopefully the WASAPI thing will help. If not, let me know of any other ideas.
Thanks for the help.