I posted this question over on AVS Forum, but haven't had any luck with answers. I mentioned it in another thread here, too, but no luck there either, so here goes: I just got my new receiver this past weekend, and I have noticed a fair amount of hiss through the speakers at high volumes with using a DSP mode (like dts:neo-6 or DPL-II) with an analog-only input or when an input is forced to analog mode. For example, if I set the receiver to the TAPE input, it's dead quiet (unless I crank it to -10 dB or higher, when I can hear just a bit of analog noise). However, if I turn DPL-II or something similar on at this high volume setting, then the hiss volume rises substantially. Of course, this is at very high volumes and isn't generally noticable in normal listening -- there hasn't been a source playing when I noticed the hiss. Plus, it's easily avoided, because I don't hear any additional noise when using DSP modes with a digital signal! What I'm wondering is if this is normal. All of my older Sony receivers (STR-DA50ES and STR-D915) exhibit similar behavior, so I think it's just the nature of the beast. Still, my mind is on it now, and I probably will never use DPL-II or similar processing modes with analog-only sources. If you own a 'DA4ES, please check for this hiss before you reply and say you can't hear it...it's something you wouldn't likely notice unless specifically checking for it, as I doubt many people frequently applying DPL-II or similar algorithms to non-digital sources.