Does your EWS64 also "hang" in some applications after some minutes?
Well, WHY does the EWS64 seem to CRASH?!
This sometimes happens when I select a midi-bank or a midi-instrument that is currently not loaded in the setmanager.
(This is definitely a bug, ain't it?!)
Sometimes, only a PART of the synthesizer seems to crash (The part responsibly for all parameters like FX-send, Filters, Mod-Wheel..) while the plain note-playing feature stays "alive".

Did you also experience those "DMA-loops" (as I call it, when one DMA-Block gets played over and over again and can only be stopped by terminating the program - so automatically "closing" the audio-engine)?
I experience those loops in flash-movies quite often.
If I don't stop that flash-movie in 1 minute, the EWS hangs totally and I have to reboot the system to get the EWS working again.
(I found out that disabling the hardware-based multi-buffering support helped a bit)

But what's wrong with the whole system?
- the Gigabyte 7IXE4 Board?
- winME?
- the newes EWS64-Software (except that super-hyper-crappy Setmanager 3.15)?

Producing music is just plain frustrating with that stuff.

What about a MAC with audio software and some external samplers and synthesizers?
Well, it may cost about some 10.000$, but it would probably WORK as expected...