|Open up the Volume Control and you'll probably see slide bars for Volume Control (the master slide bar), Wave, Microphone, etc. If not, go to Options > Properties > enable Wave. I like to set the Wave maximum and then use the master Volume Control to modify sound levels.|
That's just the operating system's sound setting. You also mentioned the hardware level: the speaker, but don't forget about the application's setting. Online video players and programs like Windows Media Player all have sound options too, so make sure they're all set appropriately.
Apologies if I don't respond to your reply immediately. I don't check this site daily, but you're welcome to PM me as a reminder.