2 questions (HDMI audio & XBMC)

[ronbaby]

I have an older laptop that I haven't been using much but I want to see if it can serve as a media player. It's an MSI X340 and it has an HDMI output port which I have wired to my Sony STR-DH520 A/V receiver, which in turn is hooked to (a) my plasma TV and (b) a pair of decent speakers... well... 4 of them, actually. I've played some test videos on it using SMplayer, and by and large it can handle videos with the range of bit rates I'm interested in (e.g. up to about 12Mbps... I don't really care if it can't play Blu-Rays).

Anyway, I ran into a small problem that I need help with and I also have an additional question. (Note that I just updated to 0.8.6 and the problem is still there.)

The problem:

I can't seem to get the thing to output audio out through the HDMI, even though I already checked and Windows 7 itself *is* properly configured to send audio out via the HDMI... i.e. the "test" function does cause the left and right speakers to make tones in sequence.. *and* even though I checked the audio settings in SMplayer itself and it *is* set to output to "dsound (1... SONY AVAMP HDMI)". So what am I doing wrong? What should I check to fix this? (Note that playing the same file WITHOUT TOUCHING ANYTHING but with either (a) Windows Media Player or (b) VLC _does_ cause the audio to go out the HDMI, to my A/V receiver, and thence out to my speakers, as desired.)

So now, my other question:

I kinda like the GUI provided by XBMC, but at present it sorts sucks at playing WMV files. Fortunately, the developers have made it possible to use XBMC but have it invoke some "external" video player program. I'm thinking that XBMC+SMPlayer might be a good combo, since SMPlayer seems to do very well with WMV files, but I'd like to know if anyone has ever tried anything like this. Or am I way off base here, and should I instead be looking into having XBMC invoke mplayer itself directly?

Thanks in advance for any replies/enlightenment.