Hi guys, First post and im no expert so go easy on me!

So my first sq install has been quite a learning process..!

I've managed to get everything running and nothings blow up (yet!) so that good!

I'm having a few problems however.

Its a VW golf mk5 gt tdi for reference and the install is as follows. Iv got an Audison Bit Ten in the car along with a Denon DCA-800 amp. Im running all this from the factory sat nav head unit. Switched everything on and there is a hissing noise coming from all the speakers. The amps a 6 channel and its powering factory speakers in each of the 4 doors. Ive attached female phono ends onto the line out behind the headunit and the same again on the input at the bit ten and run an rca cable to connect the two together (headunit to bit ten). Could this be the cause to the hissing?

Second problem is that when i turn the volume up to a certain point the speakers start popping. Could this be due to the amp over powering the speakers?

I've got all good quality cabling by audison and i know all my connections are good.

Also the rear fader has seem to have vanished from the balance/fader menu on the headunit options window! Why is this!

Any help would be kindly appreciated.