The other day I was watching a movie at a friend's house (the excellent Mrs. Henderson Presents , starring Judi Dench and Bob Hoskins, if you must know), and she complained that the surround sound in her home theatre never seemed to work. I'd watched a movie there once before but hadn't really noticed the lack. This was partly due to the fact that the film ( Welcome to Collinwood , which is also very good) was not the sort of blockbuster presentation that has you listening for fancy effects in the first place, but mostly because–as a loud-rock-music listener who grew up in the 1970s–I'm naturally disdainful of those tiny speakers sold as all-in-one audio solutions for the home. Generally, I feel it takes large speakers and a lot of power to supply sufficient volume to let you properly hear Blue Oyster Cult, Steve Wynn, Hüsker Dü, Deep Purple, or the Monkees. I may not always employ all that force, but I like to have it on tap for special occasions like celebrating Tuesdays or Gordon Campbell's birthday.

However, this friend only uses her home theatre for movies and doesn't show any signs of liking very loud music. And a quick walk around to all the speakers confirmed that only the front left and right channels were working. That was odd. So the process of elimination began. First, the DVD player didn't seem to have any buttons or controls that suggested it could be set to restrict the output to just stereo sound. Sure, there might be some obscure on-screen menu selection, but that could wait until a bunch of more obvious possible causes were eliminated. For example, maybe the actual wiring was damaged. But my suggestion to start cutting into the walls was met with a glare and the comment that it wasn't too likely that three out of five wires would fail. I decided to reserve judgment until I'd looked at the back of the amplifier, where a disconnection was more likely to have happened anyway.

Next, I checked that the DVD player and home-theatre receiver were joined together in the right way, using one of the connection methods that allow multichannel sound to flow (i.e., not just a pair of RCA cables). Those methods would be a fibre-optic cable (or TOSLINK, for "Toshiba link", after the company that developed it), a digital coax wire (which carries a stream of digital data like a TOSLINK but is a regular wire made of metal), a set of six analogue RCA cables (one for each speaker and the subwoofer), and an HDMI cable (High-Definition Multimedia Interface, which also carries all the video information). In this case it's a TOSLINK, and although these cables hook up in a finicky way, if it weren't plugged in correctly there'd be no sound coming through at all.

Then it was time to see if the wires coming out of the amplifier and heading to each speaker were attached firmly. But that's really a lot like work and would best have been facilitated by pulling the amp out of the rack and angling it to catch the light while balancing it on my knee and using one hand to tug at the wires one by one. And doing so would also require that there be enough slack in all five pairs of wires (plus subwoofer cable) that the amp could actually be pulled out that far without any mishap that might result in the amp being dropped (since it's already way up at the height of my neck to begin with), the entire shelving rack toppling forward onto me (like something from the Buster Keaton movie we might watch next week), or my chances of sleeping with her being otherwise adversely affected.

So just as with the DVD menu settings that may or may not have existed, I decided that testing the wires could wait until other, simpler things had been tried. I went around to the front of the amp, which turned out to be an entry-level Yamaha model a few years newer than the high-end one I used to own (a difference I thought it wise not to comment upon, partly because of the lack of romantic advantage, but mostly because a mere $1,000 difference in audio power seems insignificant when the cheaper amp is connected to a TV screen large enough to hide an automobile behind, while mine never met a TV larger than 32 diagonal inches).

I know that on a Yamaha the Auto setting displayed on the front doesn't mean that the amp automatically detects the type of input and selects the appropriate one (as you might expect), but rather that when it starts up it reverts to the setting it had the last time it was turned off. I started pushing the button that manually cycles through the audio modes. A long series of bogus "effects modes" passed by–fake jazz clubs, stadiums, all kinds of crap. (Next week, I'll explain why I hate those so much.) Eventually the magic words appeared: Dolby Digital. The speakers at the back of the room and the centre speaker came to life–the problem was solved. At least we thought it was, but the next time the system was powered up, the same trouble occurred. Obviously the hardware and the connections were fine and the real issue lay elsewhere…