You can't tell me this is the fault of the Window Task Manager right?
I can, and I will
When you looked back at the old threads, you would have seen the SPECTRUM example that was taking 0% CPU flat on a Celeron 300, according to Task Manager (and Perfmon - they use the same data)... that's MP3 decoding, performing FFT calculations, and displaying the spectrum - I think you'll agree that would require atleast a bit of CPU
That right there is proof enough that Task Manager is practically useless if you're looking for accurate measuring of CPU usage. WinTop/Win9x is much better. For more accurate measuring on NT-based systems, you'll have to use proper/dedicated profiling software.
The way to get some CPU to suddenly appear in Task Manager is to increase the timer resolution. This applies to all processes, ie. any app increasing it increases it for all other apps running too (if you see a media player magically using 0% CPU, load up an app that increases the timer res and watch the player's CPU start to move
). But even then the numbers are obviously rubbish. For example, we know the update rate of BASS is 100ms (default) - that means it's using some CPU every 100ms, but Task Manager shows some CPU use for a second, and then none for a few seconds, and then some more for another second, etc...
Anyway, to allow a sync latency of under 1ms, BASS sets the timer resolution to 1ms. BASS doesn't actually use any timers, but the timer resolution affects all "wait" functions (eg. Sleep, WaitForXXX), and the default resolution of 10ms is not sufficient for precision syncing.
The reason no CPU showed in the "SPECTRUM/Celeron" example mentioned above was that in the old BASS one could disable syncs, which meant that BASS didn't increase the timer resolution... if I disable the timer resolution increase in BASS today, Task Manager will again say 0% CPU.