l322 speaker problems

Hello, anyone know the answer to the following?
My n/s rear door speaker began whistling when driving the other day and I cannot get any music out of it. The front n/s speakers seem not to be giving out any sound as well but not whistling?
Any clues as what could be the problem?
cheers tim.

Would help to know what year L322. What audio system (BMW or Ford) and if hi line or low line.

Later ones (post 2005) with Ford/Jag based infotainment systems were all Harmon Kardon of some description. Amplifier in N/S/R cubby hole along with a lot of wiring. Re-seating all the plugs often cures faults on these.

Check to see if it has the waterproofing bit fitted over the units in that cubby. The side screen can leak and make them all wet - LR released a retro fix for this. Obviously water in there will wreak havoc.

You've not got that now that's what I call whistling CD in have you?