Audio Systems: How to connect AV Receiver and Amp together

Question
Dear Sir,

I can't listen to the tuner and when playing movies, the center speaker volume is quite low compared to front left and from right speakers and subwoofer (that's all the speakers I have)

This is my set up:

AV receiver: Marantz NR1501
Integrated amp: Marantz PM-11S3
Blue ray: Oppo BDP-95

Amp is connected to blu ray with RCA cables as "Line 1" source. Blu ray is connected to amp from "stereo audio out"
Receiver is connected to blu ray with HDMI

Amp and Receiver are not connected to each other

Problem:
- I can't hear anything from the radio when set to tuner
- When playing movies the center speaker volume  is relatively low and weak compared to the front speakers and the sub (so when there's an explosion etc I have to quickly turn it down, through my Amp volume control)
- Because the receiver is not connected to amp, therefore I am assuming its probably useless for me to try to tweak the sound on the receiver

When I listen to CDs from the blu ray player ... All is fine.

I hope you can help me. Thank you very much beforehand .

Reza

Answer
I think you must study the owners manual for hookup procedures. There are so many possibilities with these units that you must have all the right connections for your system.

The manual is quite clear on hookup procedures.

You say there is no connection from receiver to amplifier.  Seems you must have that in order to pass the output signal from rcvr to amp.  If both units have hdmi connections you be able to solve the problem with an hdvmi cable between the two units.