I have my PH-p4400 hooked to an externel 70W amp and of late have had distortion in two of my speakers so I disconnected the 70W external Amp and ran speakers straight to PH-P4400 to isolate to see if where problem was but there is no (very little) audio hooked up this way. Is there some setting that switches from pre-amp to amplified output or do I hook speakers somewhere else on the unit to use the amp in the P4400. The external amp was hooked to the Front jacks in the back of the P4400, Tried the Back jacks but same problem. I see a couple of female jacks marked L R but assume these are for external input thanks - Dale