I know what your thinking... "check your audio settings"... but allow me to explain further, for I am truly baffled as to how I lost these sounds!
ISSUE:
When starting up or loggin in, there is no "Start Windows" sound file that is played. When shutting down, restarting, or logging off, there is no "Exit Windows" sound file played.
MORE INFORMATION:
1) All sounds play normally once Windows is up and running, including the "Start Windows" and "Exit Windows" sounds found under Audio Properties.
2) Both sounds play when signing into my Admin account, just not my personal account that I run under normally. Under the Admin account, I can see no differences in what services I am running or what settings I could have possibly changed.
3) I've changed no settings to my knowledge that would effect ONLY the startup and shutdown sounds.
4) All other programs, such as MP3s, viedos, games, and windows sounds play normally.
5) All sound card drivers are up to date and functional.