How do I fix crackling speaker?
First you must determine if the crackling is from distorted signals or weak connections to your amplifier or music source, a sound coming from rotted/non existent surround(if its foam). A voice coil rubbing in the former gap, or the tinsel leads slapping against the spider. If the speaker has a vented voice coil, there can be dust that has entered from the back of the magnet, but that usually doesn't create noise and it cannot possibly occur in a sealed speaker box.A rotten old surround can be easily repaired with a speaker recone kit, and if you know the impedance of your speaker, you can wind a new voice coil to adopt to a new former, and speaker leads can be glued to the cone or spider. But honestly, if its a cheap speaker its easier to just get a new one.
I like to listen to fm radio without starting the car. Does it drain car battery?
Not perceptably, whilst the radio does use some power unless your car had a powerful amplifier the radio won't use much power at all. A bigger problem is that if you're switching the key to 'accessory' or 'ignition' to listen to the radio then you might be accidentally switching on other devices (eg fan, lights, seat heaters, etc) that do use significant power and will drain your battery.
Installing 6x9 speakers in Peugeot 106?
I have an 02 Peugeot 106 Independence, and I would like to install 6x9 speakers onto the parcel shelf. The car has no rear speakers, so how would I lead the wires from the head unit to the back of the car?