Today has been a joyful day at work, not the least of which is because I received a nice Christmas greeting from Sony.

This was my second Christmas card from Sony.

And it was really just a nice wrapper to cover a preview disc of “Patapon,” the PSP rhythm-war game I wrote about last week.

The disc will certainly get some play during my holiday break. But first, it is motivating me to post, because it reminds me of something I’ve wanted to ask all of you:

*Multiplayer readers, do you often play video games with the sound off?

Is that an absurd question?

Hear me out…

(And also keep reading if you want to see the nifty interior of the “Patapon” card)

I was wondering how many people play games sound-free after I played “Patapon” at the Sony preview event. “Patapon” is a rhythm game, so you really must play it with the sound on. That could pose the game a problem among the PSP gamers I see every day. Those PSP gamers ride the New York City subways. There are a lot of them (see the Stock Report on the right for the specific count). And many of them — I would say at least half of them — play their PSP on mute. They use no headphones, no volume. They play it silently.

I’m amazed by this phenomenon. Isn’t the music in a game essential? I’m particularly surprised when I see people playing music-heavy games like the PSP “Grand Theft Auto” games. Why wouldn’t someone want to hear all the radio stations?

I’ve noticed the same thing with people who play the DS and the GBA on the subway. So I guess a lot of people just aren’t playing “Beats” or “Elite Beat Agents” or, for shame, “Rhythm Tengoku“?

I thought this no-sound craziness might be a portable-gaming thing. Maybe people would rather listen to their iPods or don’t think portable gaming music isn’t worth listening to. But a guy I mentioned this to last week told me that he plays racing games on his console without the sound. He said the squeaks of virtual car tires are nice to hear a few times, but, after a while, it’s something he can live without.

Really. So who else out there plays games with the sound off? Which systems do you do that with?

P.S. The Christmas card with the “Patapon” disc has a nice message inside. Take a look: