Hi,
Thanks for the reply, Matt. To answer your question, Winamp doesn't hiccup at all during playback, no matter how I use it...
- maximized without visualization (just the spectum analyzer in the main window)
- maximized with various AVS visualizations in a window
- minimized
- fullscreen AVS visualizations at various screen resolutions
- other visualizations (e.g. Geiss)
In all cases, the CPU utilization (as reported in Windows Task Manager) of Winamp is only about 2-8% (typically 4%) without visualizations active, 70-85% with AVS active (windowed). As I watch the CPU speed meter in my monitoring app, the Athlon 64 remains at 800MHz without visualizations, and jumps to 1.6GHz-1.8GHz when AVS visualizations are active. Winamp does not seem to cause the CPU speed switching to jump up and down like Media Center does... it's a steady 800MHz without AVS, and with AVS, it remains at/near full-speed. I can try to simulate the speed jumps by rapidly activating/deactivating visualizations, but Winamp never glitches.
Contrast this with Media Center: CPU utilization 15-25% with no visualizations at all (and occasional hiccups), 40-90% with visualizations (and frequent audio hiccups), depending on the current visualization. Meanwhile, CPU speed fluctuates between 800MHz and 833MHz without visualizations, and jumps between 800MHz and ~1.6GHz with any visualization.
It seems like Media Center's CPU usage is close enough to the borderline conditions, even without visualizations, to cause the CPU clock speed to momentarily spike, then drop back to 800MHz, and a glitch happens every time. On the other hand, with visualizations active on-screen, the CPU usage is much higher--- but not high enough to keep the clock at 1.6GHz continuously, and again, when it drops back to a lower speed the audio hiccups. As I watch Task Manger's performance graph, it seems that Media Center's CPU usage is a lot more "spike-ey" (or inconsistent) than Winamp's, with or without visualizations. This inconsistency appears to be giving the AMD PowerNow fits, and it can't make up its mind about which clock rate to stay at.
So, to make a long story short, the clock kicks up and down with Media Center, but not with Winamp. Mind you, I have all the latest drivers for my system (including the soundcard and the AMD PowerNow feature), and I'm not using anything fancy like synthesized 3D sound, just basic stereo. FYI, my disk drives are using UDMA mode, so disk access doesn't seem to be a problem.
If I disable the AMD PowerNow feature by setting my Windows power management to "Always On" or "Home/Office Desk", the system runs at 2.0GHz continuously and the playback is far smoother.
I really hope I can get this resolved, it's driving me nuts. I kind of created a workaround by adding Winamp to Media Center's "Play Now" menu... yeah, yeah, it's a copout, but what can I do...
aimhere