05 Tucson, audio upgrade

I need some help with my 05 Hyundai Tucson. I'll list out my audio system as it is. Android 2-din head unit. Factory 6-channel amp in the boot. factory 7 speakers, 4 mids in the doors, 2 tweeters in the front doors, and powered sub under the driver's seat. The head unit is connected to the factory amp, using the existing wire loom. And the Sub amp is connected using the RCA. The head unit has a 1-ch sub pre-out. Now. I wanted to start my audio upgrading with a better subwoofer, not too much louder, just better. SSL SMCM200 200-watts 1 Channel Amplifier Rockford Fosgate P1S4-8 200 Watts RMS 400 Watts Peak. The bass amp (SSL) has its own power supply from the battery, and ground to chassis. As for the remote wire, I tapped off of the existing remote wire which goes to the factory amp. Now before you guys start telling me that I won't get any additional bass from that setup, I know this already, which is why I have a preamp to install next weekend. My problem is, that every now and again, the factory amp won't switch on. But the bass amp will always switch on. So I did a quick test. When I Unplug the wire harness for the bass amp, the factory amp comes on right away. Then when I plug the bass amp harness back in, everything works as normal. Did I miss something in my wiring? Any help or explanation would be awesome.Objects in the rear view mirror, got Chopped!

I would assume the new sub amp would be considerably louder. as for the remote, 2 things. Add a relay from the radio turn on wire then output to the 2 amps or just diode isolate them. IF you really want to make sure it works, add the relay and isolate them. My guess is that the headunit does not have enough power to trigger both.

Thanks RS, I had a feeling that the relay would most likely solve the problem. But I were to use the diode as well, where would it be connected?Objects in the rear view mirror, got Chopped!

About the sub and sub amp... The bass level would have been controllable if the deck had that option, but alas, it only has an 9-band equalizer app, and no bass boost features what-so-ever.Objects in the rear view mirror, got Chopped!

It has Sub out but no Sub control? That is surprising. What is the model of the head unit? I know that sub pretty well, that should out do the OEM sub pretty well unless the amp just doesn't cut it. What kind of enclosure do you have it in? That little 8 is impressive in most install I have done.

the deck is a "Carjoying" JY-UQ128 (Chinese brand) Sub is built to spec, in a ported box.Objects in the rear view mirror, got Chopped!

BTW, I can vouch for that little amp... I bought it after a friend of mine did. he had it hooked up to a JL Audio 12" in a spec ported box. It was shaking up the car properly!Objects in the rear view mirror, got Chopped!

The system has been fixed, he relay solved the problem. But... there was one thing that the installer wired incorrectly. Apparently, he thought it was a good idea to connect the bass amp remote wire, to the factory amp ACC wire. He must have thought that it would have provided enough current to switch on the second amp. Anyway, I corrected the wiring, and now all is well. Thanks for all the help. Close threadObjects in the rear view mirror, got Chopped!