The 2200 will produce very tight and consistent peak level control with no overshoots, so if there are overshoots there's something wrong with the interfacing to the TX (possibly the active stereo generator in the TX as Scott suggests) or the unit is bad (which is very unlikely). The same goes for loudness. 2200 is fairly loud, it can even sound louder than the 5-band units with some program material. Also, you shouldn't hear any obvious sibilant distortion unless there's something wrong with the setup (or the unit).
You should re-check the settings on the TX and the connection to the TX. Like Scott says, feed the processor directly with high quality audio, to see if the problem is ahead of the processor. Check the modulation level. Check the input level into the processor. It would be wise to load a factory preset for the time being, just to rule out possible maladjustments. But most likely, the problem is not the processor, but something else...
Regards,
Goran Tomas