crackling in only one channel when using bluetooth to a receiver

[wpatters1229]

This is making me nuts. I have a projection TV that works fine, and connected to it is an Apple 4K TV device. From that device, I transmit Bluetooth 16-bit sound to a Pioneer receiver. When I scroll through icons on the Apple TV home screen, each time, there is a crackling noise coming out of the right channel. It can also be heard in my earphones that receive Bluetooth from the receiver via a third-party transmitter connected to the right and left channels of the Zone B output.
I have swapped the Apple TV with another one, and nothing has changed.
I thought it might be a problem with the receiver, but I hear it in the right channel only of the headphones, and if the headphones are off, I can also hear it in my surround sound right rear speaker, and I am assuming the right front speaker. I can not tell about the front speaker since it is background noise.
Here is the crazy thing. If there is a movement or change from one thing or another on the Screen, the crackling noise happens, but then about 2 seconds later it stops. If I am watching a show, it is in the background all the time until I hit pause, and then it stops after 2 seconds.
I believe it has something to do with the Bluetooth transmission to the receiver, but not sure. The Apple that is providing the Bluetooth transmission is only about 12 ft from the receiver.
Does anyone have ANY ideas on what would be causing this? I can ignore it most of the time, but my OCD is making it hard to do.

 

[Keith_W]

Welcome to ASR!

I suspect the crackling sound is due to packet loss. Most people say it sounds like stuttering, rather than crackling. With crackling, the sound is still there, but there is crackling noise superimposed on top. With stuttering, sound stops and starts with silence in between. Crackling is what you hear if you drive into an underground carpark whilst listening to AM radio. Stuttering is if you do the same whilst listening to digital FM radio. So which is it? If it's crackling, it's analog noise. If it's stuttering, it's digital packet loss.

The fact that the sound only occurs when you interact with your Apple TV suggests that you are somehow losing packets for whatever reason. I would think that Bluetooth is the most likely culprit. My laptop is only 1m from my bluetooth speakers, but I still get stuttering unless I point either the transmitter or receiver a certain way. Although some flavours of Bluetooth have a theoretical maximum range of 100m (300ft) I don't believe it. It is notoriously unreliable. I suggest you try moving your Apple TV closer to the receiver or trying a cabled connection.

 

[wpatters1229]

Yes, it is the crackling. The problem is that the projector is across the room, and the Apple is connected to it via HDMI. I could use a long HDMI cable and then move the Apple close to the receiver, but having the HDMI cable across the floor would be a problem. The only reason for doing that would be proof of the cause. What is weird is that it only comes out of the receiver on one of the two stereo channels...the left one. I switched the outputs on the Zone B (which go to a headphone bluetooth transmitter) and it moves to the other channel, which says it is coming out of the receiver. Do they make a repeater for Bluetooth? That might be the answer. Much the way they do for WiFi. I could put the Bluetooth repeater close to the Apple and then point that to the receiver.
I know it is driving me crazy, but being retired and a perfectionist, it is now my life goal!!

 

[Keith_W]

Diagnosis comes before treatment. Unplug your Apple TV from HDMI, and move it next to the receiver. I presume you can still control it with your iPhone/iPad. Play some music. If the noise persists, it's probably not Bluetooth.

If you are absolutely certain it's a crackling sound and not stuttering, then it's analog noise. You only get analog noise after digital-analog conversion, which means it's the AVR. But I am not entirely sure if you know the difference between what crackling and stuttering sounds like.

 

[wpatters1229]

I figured it out. I had another Bluetooth device that could receive and transmit. Avantree Oasis B – Bluetooth Transmitter & Receiver. I set it up to receive and the output optical, which I plugged into the optical port on the receiver. The receiver is input only. I then set up the receiver on the TV selection and it started using the optical input. The crackling was gone, and the volume on the Apple was greater. It also did not affect my earphones receiving via Bluetooth from the receiver Zone B. All is good!! My conclusion is that the Bluetooth was too weak just from Apple, and the Avantree gave it that extra boost. I found that tip in another internet location...got to love the internet!

 

[wpatters1229]

Diagnosis comes before treatment. Unplug your Apple TV from HDMI, and move it next to the receiver. I presume you can still control it with your iPhone/iPad. Play some music. If the noise persists, it's probably not Bluetooth.

If you are absolutely certain it's a crackling sound and not stuttering, then it's analog noise. You only get analog noise after digital-analog conversion, which means it's the AVR. But I am not entirely sure if you know the difference between what crackling and stuttering sounds like.

I fixed it. I put up my fix. It was BT and being too weak from the Apple. All fixed and now great sound