Picking up interference and I’m 94.386% sure it is a loose connection somewhere because it is intermittant from non-existent to soft to really bad and yes, bumps sometimes affect it but it is inconsistent and that has me flummoxed. The noise from the speaker is static and occassionally crackling (listen to the opening drums to Hot For Teacher. That’s the sound.) It is independent of volume meaning increasing or decreasing the volume doesn’t affect the volume of the sound however it goes away completely if there is NO volume i.e. the stereo is on standby or the volume is turned all the way to 00. Oh and very rarely there is a whistle that varies in pitch with the motor RPM - higher RPM = higher pitch but like I said very rare.
I believe it is just the rear speakers (why I haven’t tested it with the fader I don’t know) so with all of these symptoms where should I be looking?
Are you SURE it’s just one set of speakers? Sounds can be easily misidentified in a car, where you are much closer to one speaker(s) and have your back to others.
Does it occur with all sources (FM, CD, USB, or whatever)?
I doubt it is a speaker problem, unless the speakers are self-powered (which is fairly rare, with the exception of some subs).
The whistle you describe is very common for engine noise. A simple filter in the power lead may cure all the symptoms.
The crackling noise is typical of some other types of problems.
something in the radio or amplifier has failed and now radiated noise is getting in and being amplified. given that you say the noise is constant (not varying with volume) and only goes away when the radio is off or at volume step 0 (when the power IC is put in mute state) I’d say it could be anything from a bad solder joint, bridged trace, or one or more failed capacitors somewhere in the audio path.
I’ll use the fader and balance to determine which speakers and update.
All sources including AUX
No self powered speakers.
When I got the car, the whistling was constant. I pulled out the stereo and the previous owner had the microphone cable in a loop. I assumed an inductance issue and removed the microphone. No problems after that except a couple of times. It’s the intermittance that confuses me.
Since the noise is common to all sources, I would take two preliminary steps:
Check that your ground wire (usually black) is firmly connected to a good body ground point.
Purchase and install a simple car power filter in your power conductor. They cost about $15 to $20 on Amazon.
I suspect that you will see a marked improvement. There may still be some crackling, especially if your splices and connections are not 100% good, but the whining and engine noise should decrease significantly.
I had a similar problem a few years back. (Hyundai Santa Fe with a Monsoon sound system.) Took it to a local shop to have the front speakers replaced, only to have the problem persist. I think it was someone here who suggested that it was the amplifier going bad. I thought about replacing it but the vehicle was over 10 years old at the time so I just decided to live with it since I didn’t think I’d have it much longer. Funny thing is, after about a year it just “fixed itself” and I never heard it again.
Drums to Hot For Teacher sounds like they’ve deliberately added clipping in the mix.
Are rear speakers in the sun? You may have a slight tear in on of the cones.
If you have mp3 input, try recording a constant 300Hz sine wave and square wave.
Play them while monitoring with your smartphone audio range oscilloscope. FFT should give you the frequency distribution of the distortion.
Where did you get it installed? Please don’t say best buy or a big box store.
Many people think a wire splice is stripping the harness wire and wrapping the actual units wire around it with electrical tape. This causes crackling, chirping and whines.
My money is on a loose connection. If it is mostly from the rear speakers check them out first or pop off the bezel around the radio and unscrew it (have a set of TORX drivers just in case) and check on it.
If that is the case, get some solder and butt splice connectors and crimper. Should only take about 20 minutes to patch it up.