Sound problem: GPWS ok, but no A/T - AP - disconnect

Hello,I have a sound problem. I read several threads about missing GPWS sounds; they are o.k. on my machine, but the warning sounds for A/T and AP are often missing - not always. Sometimes a restart of FS2002 helps, but sooner of later while flying the sounds 'get lost' again.I tried different sound hardware acceleration settings, doesn't seem to help (exactly: sometimes helps, sometimes not). I also tried to remove fssound.dll -> no effect.Any idea ??Matthias Huck, Oelde, Germany