The only recent unknown song to go more than a week without being identified now has a name. Unknown Song #4 is "Showcase" by William Soden. It's actually an NFL Films song, but it unfortunately does not seem to be available in the NFL Films library contained on APM's website. I guess it may only be on LP and not on CD. You can easily find it on Dave Volsky's channel on youtube, though. Special thanks to PYLclark on youtube for letting me know this track's identity.