Monty's example files made me realize that my computer's sound chip is probably kind of lo-fi. No, I couldn't hear anything in my headphones when I played the

Monty's example files made me realize that my computer's sound chip is probably kind of lo-fi. No, I couldn't hear anything in my headphones when I played the 30Khz/33Khz tones. In comparison, I heard something after it stopped. Somehow it was quieter during the playback. Does it make any sense that my computer is better at making no audible sound when it's asked to play a loud inaudible sound, than when it's being asked to play nothing?