2012 D4 TDV6 Harmon Kardon sound issues

[Fozzie]

Hi all
This one is doing my head in

2012 D4 TDV6
Harmon Kardon (not logic 7)
With the large screen

Everything was working fine and then one day - no bass or lower mid range sound

The Subwoofer still works but everything else sounds tinny

Action so far
Via wreckers
Have replaced
- the Head unit
-And AMP(in the rear of car)
-the MOST channel looks to be working
-It doesn’t matter where I put the fade/balance same ****ty sound regardless of speaker

The questions on my mind are
1. Is there some other device the processes the audio between the AMP and Speakers
2. are the speakers to blame (if so how to 4 or so speakers all go at once?)
3. I haven’t replaced the screen unit - but surely that doesn’t process the sound?

What am I missing
Need my tunes

Help??!
Ps anyone want to buy a spare head unit or amp

Thanks
Foz

[DiscoJeffster]

@cambo will hopefully be along to advise.

[Fozzie]

Actually bit of an update
In terms of sound it’s sort of sounds like poor Mono

I dunno grrrr

[Fozzie]

Help anyone ??

[Tombie]

Patience... You could message "Old Jaguar" on FB or Cambo on here.

Not everyone reads everything daily or hourly!

[Eric SDV6SE]

Actually bit of an update
In terms of sound it’s sort of sounds like poor Mono

I dunno grrrr

Sounds to me you've had Donna Summer up too loud and burst a speaker cone.....

[veebs]

What input are you using? Same problem on all sources?

I've had ****ty sound in the past myself - turned out to be a loose headphone jack on the Aux input...

[Fozzie]

Hi Veebs

All sources
CD
BLUETOOTH
RADIO

very frustrating

[Fozzie]

Sounds to me you've had Donna Summer up too loud and burst a speaker cone.....

Maybe John Denver

But it’s on all speakers
Unless the lower to mid range is only delivered by the front

Even then… to blow 2 speakers at exactly the same time ?

There must be something central I have missed???

[veebs]

Have you checked the fuses in the car?

I don't have a 2012, or even my own D4 to check, but I would start with:

Fuse 2 in the upper compartment (behind the glovebox) - should be a 10A
and Fuses 41, 64, 67 and 68 in the lower compartment

Fuse Box Diagram Land Rover Discovery 4 / LR4 (2009-2016)