Hi everyone..

 

I bought chinese headunit(Funrover ls001) and as many others i didn't get any sound from it after installing.. I have octavia vrs 2006.

I found a solution on this forum, to use original audience radio connected parallel to power up an amp. As this worked, used another option for less space usage and took out main board and mounted a switch. Thanks to author for the tips!

 

Well i got sound, and when loud its very nice quality, maybe even better as with audience maybe the same, can't say right now..

 

But the problem is a constant hum in the background.. Even worse, when i turn od Disc app for DVD/CD player i can hear MECHANICAL sound from dvd player in speakers??? If i open music app, to read from SD, this mechanical noise goes away but then when on pause or low volume i got constant hum and static noise, you can hear difference when you slide finger over the touch screen.. Sometimes it also sounds like some radio interference or something, strange noises almost like sounds.

 

I did check ground, i even tryed connecting hu directly to battery - just before i wrote this but still there.. I also tryed connecting ground to hu's housing, and some other tricks i've found online.

 

If i power on the car, it's not heard that much becouse of engine running, but still loud enouh to hear it and its very annoying to me. It also makes bad sound quality at low volumes as you can hear it and some cracking i think too..

 

Any ideas? Would some kind of ground loop insulator fix that problem or not? The noise is there with engine on or off, and doesn't change with rev's or anything like that.. I tryed without antenna and nothing changed. Its really the only thing i need to fix all this complications to get this hu working almost drove me nuts..

 

Btw the hum goes away when volume on 0, anything other then 0 is same noise and doesn't change much with higher volume, maybe just a bit.

 

Thanks,

Matevz

I've made video, so you can hear how it sounds, at the end of video i did turn to "0" and back to "1" volume, so you can hear the buzz coming in..

 

https://youtu.be/AAXTTqbdbWo

Hi, I have the same problem with the same product.

You find the solution?

 

I'm an engineer and I deal with audio a lot.

 

My first instincts with these symptoms would be to check all the earths are OK, coming from the same source (ground loops in earths can cause some really odd symptoms) and the power supply is adequate (thick enough wires) and clean.

 

If there is a speaker earth or the earth on the aux socket going directly to ground somewhere or the unit gets its power or earth from something like the BCM, this could cause all kinds of audio imbalances. Does the symptom change when the engine is running or if any particular piece of kit (like the HIDs, if you have them) are switched on? Does it affect some sources audio sources (radio,CD,aux) more than or differently from others? Can you run detach the power supply from the head unit and run a temporary wire directly to the battery? Does the fault change or go away if you do? Can you try disconnecting all wires from the unit other than the power and speakers?

 

It might be worth winding the power supply wires onto a ferrite ring to see if there's noise coming up the power supply from other electronics.

 

Happy to try to help if you need.

Edited 31 March, 20179 yr by Papfox

In case your ground is not the problem as you say you have checked it before, you can try to see if the radio gets some interference from some other source. Could be something transmitting wireless signals into your radio circuit.

Because of aftermarket radio unit it could not be shielded well enough to block potential electromagnetic waves, so you can maybe try to cover your unit with some appropriate shielding to test this out. 

If that is the case you can try to cover inside of the units plastic with some copper spray perhaps?

The symptoms are same if engine is running or not. I doubt it has anything to do with grounds.. Did a few test described online. With factory unit there was no noise, but factory unit did not have built in amp. Speakers are the same, so are connections. It has to be either bad shielding or components or 2amps amplify the noise so much? I dont have it connected by rcas, but speaker line. Only sub and sub amp are signaled through rcas.

 

Anyway i managed to fix the manual amplifier powering by button soldered to factory units motherboard. I used 2 timer relays. One waits until i power up the car ca. 20seconds and then signals other relay to create a contact that lasts 2-3 seconds as you would push the button.. The relay is powered from fuses, where i found switchable 12v by key.

 

Why two relays: when you turn the key, one relay would power up the amp but as you turn the engine on then, canbus will be restarted and the amp would not turn on again. Therefore i put 1 relay to wait until i power up the car and the headunit loads (20-30secs) and then that relay signals the other one to power up the amp. No point turning it on before headunit loads anyway.

There is just 1 con: if you dont turn the engine on and amp gets powered up, you then before the ignition need to remove the key and then put it back in and start a car.

 

Two relays cost me about 4 pounds from china.

 

Anyway it works great and hope it helps if anyone wanted to make things more automatical.

I ordered another headunit, but i doubt it would fix the noise.. I was told by a seller i'd probably have noise with any aftermarket unit.. 

 

Im swaping it for other reasons and issues..

On 7. 4. 2017 at 16:40, Rush56 said:

I ordered another headunit, but i doubt it would fix the noise.. I was told by a seller i'd probably have noise with any aftermarket unit.. 

 

Im swaping it for other reasons and issues..

 

Edit: no detectable noise with new unit, even sub has a more defined kick. Very surprised, and i like android 6.0 hu more then 4.4 version wise. Also very quick, boots like in standby in 3 seconds. Only con so far is parking sensors dont display on unit, contacted seller and waiting for replay if its fixable. 

 

Edited 13 April, 20179 yr by Rush56

Hi, tell me please what model is this new HU.