Problem with Fluance Ai41 powered speakers when connected to preamp

I just purchased a set of Fluance Ai41 powered bookshelf speakers and connected a Rolls Bellari pa550 headphone / preamp which is running from my turntable. This started some horrible clipping with the volume about halfway up on the preamp. I lowered the volume on the Rolls and this eliminated clipping but soon found out that the Fluance 90 watt class D amp has some sort of safety feature that automatically lowers the volume to sub par level while quickly readjusting back to where you have it set when sufficient bass response is present. I lowered the volume of the preamp more and this still persisted to the point where now I am using the preamp built into my turntable. I would rather have the external preamp because it just sounds more defined and warmer. Of course there is also the issue of having to disconnect from the Fluance's and hook back up to the Rolls if I want to listen on the headphones. Surprisingly, I read two reviews on the Fluance site where these customers had a similar issue while hooking up the Fluance P10 preamp to the speakers. Fluance even has package deals that include this preamp with their turntables along with these same speakers. If I can't trust the Fluance preamp to match with these speakers than can I trust any? Does anyone know of a simple preamp that shouldn't activate this annoying feature on the Ai41's?