SANWU TPA3116 + CSR8635 Bluetooth 4.0 - Noise Fix

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Hello guys, hoping to get some help here. I bought sanwu 2.1 3116 amplifier with an intention to use it as an second amp hidden in my car to have an option for bluetooth and aux, which I have no other way to get installed otherwise.

It's this amp:

An externally hosted image should be here but it was not working when we last tested it.


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Now, I also had other idea, to hack into car speakers via two DPDT relays and switch them between car stereo and 3116 amp, which resulted with a burned amp, as relays I sourced did not like an idea to work in parallel.
This resulted in a trace burned on a 3116 board, which I rewired, and the amp is working now.

However, I have a loud "clicking" noise in between the songs or in the songs that have quiet parts. This noise is present on all of the channels and it's level depends on the input potentiometer state, or it's low if I turn up the volume on the source (smartphone), and keep it low on the amp, or it's really high (louder then music) if I keep the input level very low and potentiometer high.

I cannot remember if there was so much noise present before the accident where the magic smoke left the amp, or it's the result of this happening.
Board has AUX input, and there is no noise when using it instead of bluetooth, no matter the level.

Is there anything I could check and try to get it usable?

Thanks!
 
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Thanks doctormord. I've noticed (looking through this thread) the the resistors this is replacing are pretty high value. Would the 1k pot have any effect at this point, or should I get something bigger?

P.S.: I'm building it into a refurbished radio cabinet, so it's more of a "feel" thing than usage
 
Simplest solution for me was the wire...

Soldering a short piece of copper cable (2inch or so) to the Bluetooth antenna sorted it out and reduced the noise to almost imperceptible levels. (best result was found by attaching the wire to the antenna at the nearest point to the edge of the board.

Follow up question... Why does this work?

I wasn't too happy reworking smd but was really annoyed by the hiss, so i decided to try this. My board is dead silent now, i've just added a short piece of shielded cable to the tip of the antenna (shield not grounded).

As far as I know, it works because the antenna sends from the sharp point, so if we take this sharp end away from the board no more interference gets induced. I am sure this could have been fixed in the design of the board, even with their additional components there. In this Stackoverflow answer is an image of the radiation profile: https://electronics.stackexchange.c...ooth-antenna-affect-the-transmission-distance

The other mods i've done is to make it a mono amplifier and remove the connectors.

An externally hosted image should be here but it was not working when we last tested it.
 

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I have the same board and have noticed that although the usual buzzing, hissing, and popping on low volumes and disconnects happens both channels, on the left channel only, I get a sort of building up buzzing then pop sound. I'm guessing that this is to do with the capacitors loading up, but why does it only happen in one channel?
Also, does your suggested fix break the line input, because I would like to be able to use it as well instead of bluetooth
 
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Hallo all, I bought tpa3116 bluetooth amplifier 2x50watt + csr8635 sannwu audio, i got problem, my module always turn off every 3 minutes or less. What should I do to fix it?
If i will to change bluetooth module, how to wiring it? Because if i cutt of power of csr8635, module tpa3116 in mute mode
 
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