I have an '08 limited with the JBL Systhesis system. When I got it the radio was junk, it only played the left channel so I got a Pioneer DMH2660 nex with install kit and a maestro kit from Crutchfield. Installed that now all speakers work but sounds terrible so I got 6x9 component and 6.5 infinity Reference speakers. Even before I changed everything I was getting bad sound out of the left front ONLY. Still get it with the radio change and speaker change. Sounds like a blown speaker. Tried 3 different speakers and all of them do it. I sound deadened the doors, no change. I changed the JBL Amp to a spare one I have, nothing. Crutchfield is stumped also. the speakers are 3ohm as that is the max you can go without loosing sound.

Any of you had or heard of this happening?

I haven’t heard of your problem but, if the left front speaker is the only bad one regardless of amp or speaker, it sounds like a speaker wiring/connection issue.

at this point, take out the jbl amp and use an aftermarket amp with enough channels for your system. youll need to run new wires directly to the amp, your radio will sound so much better when you get rid of the jbl amp. on the stock harness, youll need to figure out what is constant hot, switched hot and ground and antenna trigger.

you will need to run rca wires from the radio to the amp also.

Hey, I had the head unit replaced in my 07 as they said the factory amp was shot and bypassed it. As a result I now have now bass to speak of. Do you know if there is a way to fix that? I dont want to add something to the car that is going to restrict how I use it (i.e. some giant bass tube etc). Any help would be greatly appreciated.

if you still have the jbl sub in the back, i know its dual 2 ohm, wired to 1 ohm final load. if that sub is deteriorated, i would swap it out to a pioneer slim or rockford fosgate slim. then have a small amp maybe in the 200-400w range to power it. lot of folks here have done that.

you can also use those aftermarket sub and amp combo. i like jl audio microsub+, its very good sounding to me, those ported enclosure would be a very good upgrade, but the down side to them is the cost. if you want some cheaper, you can go rockford fosgate.

if your planning to upgrade, i would do sub and amp separated. more options and more customizing in products.

^^ I second this.. if I had to do it over again, I would just take a little extra time and strip the old JBL system out and run an aftermarket unit, amp, sub and wires out to new speakers. Even a budget setup would sound significantly improved over the factory setup.

My biggest reason to no have done it was pure laziness with not wanting to pull out my drawer system and rip apart the interior... but would have been well worth it.

Wow thanks guys! this is super useful I really appreciate both of you taking the time to share this. I suspect I will go with 'do it right' solution even if I have to save my pennies for a little while.

Thanks guys.