Terrible audio DH-SD29204T-GN Help please.

[scguy]

I own 7 Dahua cameras which include 5 IPC-HDW4431C-A cams and 1 Starlight IPC-HDW4231EM-AS and the audio problem child in the title. All but this camera have very usable audio. This camera has lots of noise. By noise I mean crackling and squeal (sounds like feedback). I've tried every available encode option, sampling frequencies and volume settings numerous times. I've tried with noise filter on and off. I've also had a piece of microphone windscreen foam over the tiny mic hole.
At this point I am hoping this is a firmware issue but I am not very hopeful. I've not found a firmware update.
Below is the info on my problem child.
I would guess I'm not the only one experiencing this. I purchased this camera from empiretecandy on Ali.

Device Type DH-SD29204T-GN

Software Version2.422.0000.3.R.T4.484.9A.NR, Build Date: 2016-10-09

WEB Version3.2.1.383637

ONVIF Version2.42

PTZ Version2.06.29.RHNVFJCA

 

[nayr]

couple things, its a PTZ so move it and see if the squeal goes away.. I can hear whine from my electric motors on my mini-black face PTZ and it seems to get worse as it gets colder.. usually moving the ptz just slightly can reduce or eliminate the whine.. its got belts and motors, the tension is causing a load on the motor I suspect.

secondly it could be external interference, I get a high piched whine out audio pickup on one of my new cameras I wired up.. but only when the security lights are on, the next time I'm up in the attic I need to add more physical seperation between the ethernet cable and the AC Power lines for my front security lights, they crossed over and its inducing noise that the analouge mic picks up.. can you take it down and bench test it to see if audio issue exists on a short prefab cable?

 

[scguy]

@nayer
Not a problem to take down and bench test. It is mounted on my back porch under the eave and as you know it only takes a "twist" to remove it. I had noticed the squeals while using the PTZ. They would come and then subside. I can run power and data to it from another source and keep it in its current location. I'll try it a couple of more ways to see if its the camera, wiring or outside influences. Thanks for responding man.

 

[scguy]

I've tested it again. Once in its current location yet running a dedicated data cable from an inside source with no obvious interference along with changing power source to a 12 volt adapter. No improvement. I then brought the camera inside and tested (multiple settings) with no improvement. Removed plate on bottom of camera just to observe the mic wire or maybe see something out of order. Nothing there. As I sit and write this my only thought is the micro sd card I used. Could it be remotely possible that it could cause interference? I would think that would be a long shot but at this point I'm obviously lost. If I reduce the settings low enough to eliminate the noise the audio becomes useless. Not the end of the world but not what I payed for either. I wondering if I just got a lemon.

 

[looney2ns]

Have you tried resetting it to factory defaults to see if anything changes?

 

[scguy]

looney2ns
That is one thing I have not done and it does seem that upon my initial bench setup the audio seemed fine. However it was in my mechanical room downstairs inside and any volume at all would create feedback. I am not past trying anything. Other than the audio issue this is a pretty nice piece. It got a good test in the blowing rain and then fog we had here in the first couple of days. The audio problem existed before that. Thanks for the suggestion.

 

[nayr]

might try another power supply? ground loops are usually the issue here.

 

[scguy]

@nayr
I powered it today with my test with a 12v ,1a adapter. Normally it runs POE. I just finished starting from default. Made no difference. I am a little surprised that there aren't others with this problem. I may be on an island though.

 

[nayr]

bummer, there's one guy on here with like 80 of em in high school gyms and I'd think he'd of reported it too..

can you attach a recording of the problem?

 

[scguy]

Here is a short video with my crappy audio.

Just when I have decided to try and solder another mic setup to the camera I viewed a motion triggered video when I let my dog back in this morning. Audio sounded almost good. Now I'm even more confused.

 

[nayr]

hrmm, if I had to guess I'd say a damaged microphone, ive got some cheap dead external mics that do that after they got wet.. you said it went through some rain, was it like this before the rain? these cameras are not all-weather rated and if it was damaged because of moisture ingress then tha'd be on you.

might as well disable audio on that camera and seal up the mic hole.. that is pretty unusable.

 

[scguy]

The audio problem existed before the moisture. I read another post where a guy had the same exact problem with another model Dahua. At least his description made me think so.Dahua Camera Audio Noise
I have audio on one of the other Dahuas on that side of the house that works fine. I really like stuff that works and may attempt replacement of the mic itself. It is located in the stationary shell of the camera with a tiny plug that connects it to the board. I'll probably need some magnification to solder it.

 

[TVT73]

hrmm, if I had to guess I'd say a damaged microphone, ive got some cheap dead external mics that do that after they got wet.. you said it went through some rain, was it like this before the rain? these cameras are not all-weather rated and if it was damaged because of moisture ingress then tha'd be on you.

might as well disable audio on that camera and seal up the mic hole.. that is pretty unusable.

This could be the point. Why the hell are you using an indoor cam for outdoor use?!? This cam is indoor use only! A damaged mic is one of the smallest problems you will get. It doesn´t matter to mount it nealry water safe, the air humidity will damaged the cam anyway. Not now but really fast.

 

[scguy]

The audio problem existed before the moisture. I read another post where a guy had the same exact problem with another model Dahua. At least his description made me think so.Dahua Camera Audio Noise
I have audio on one of the other Dahuas on that side of the house that works fine. I really like stuff that works and may attempt replacement of the mic itself. It is located in the stationary shell of the camera with a tiny plug that connects it to the board. I'll probably need some magnification to solder it.[

Here is a short video with my crappy audio.

This could be the point. Why the hell are you using an indoor cam for outdoor use?!? This cam is indoor use only! A damaged mic is one of the smallest problems you will get. It doesn´t matter to mount it nealry water safe, the air humidity will damaged the cam anyway. Not now but really fast.

Short answer. Save money, see if it will live.

 

[nayr]

some people have installed these fully exposed; and much to my dismay they seem to survive.. If anyone's had any issues related to the weather and these its been this; and thats just speculation as I have no proof this is the result of water ingress... but so far Ive not heard a single report of total failure w/this camera and I know alot of ppl did roll the dice and put em a bit more exposed than I'd of personally...

figures a cheap dahua indoor ptz outlasts other cheap outdoor PTZ's

 

[Fastb]

My IP67 cams (rating for outdoor use) have a pack of anti-desiccant inside, to keep the interior dry and prevent mist or droplets from condensing on the window or lens.
I'll bet a non-IP67 cam doesn't have the anti-desiccant packet.
The camera interior will be warmer than the outside. This will draw air in & out as the ambient air temp changes. This thermal cycling could allow moisture to enter.
"Roll of the dice" - well said, nayr....

Fastb

 

[scguy]

@nayr, Mine is not quite as protected as yours but not near as unprotected as some of the pics I've seen on this forum. The audio issue now seems to come and go. I'm not blaming it on the environment. I looked at the microphone. It appears to be the same mic as used in the cams rated for outdoor service and mounted the same way. I appreciated your comments as they stirred the thought process. I come here to learn and folks like yourself help us all. If this were a machinist forum I might be able to help others more, but it is not. Thanks again.

 

[nayr]

it might be drying out, the way a microphone works it dont much moisture to short it out... an anti-desiccant or some rice inside might be a good idea.

 

[TVT73]

Maybe you can swap the mic from another cam? You seems to have other dahuas.

I have also with an ipc-hdw4431 sometimes audio plopping and audio disturbances, although it's a wind protected 10m2 rabbit hutch. Maybe the mic quality sometimes variety?

For the cam being ip67 rated or not is much more than only a moisture bag inside. Especially a ptz has moving parts, which must be protected against water. The seals are normally missing in indoor used only cams. The next point is temperature resistance. This one is black, be aware of the sun.
Dahua has cams with ip65 rated, but this one has no ip rating.

Anyway if other ones here are using this one outside, and didn't report of problems, this says nothing. I can't recommend it in any way.

 

[scguy]

Been monitoring audio more closely for several days now. Audio is perfect for a few minutes or longer and then the annoying scratchy sounds come back, and then disappear again. I don't think it's outside interference at this point at least there's nothing electrical that I can think of that could interfere. Yesterday I took her down and inspected the camera. Zero moisture present and everything looks just as good as it did when I first got it. I tried another mic, utilizing a de-soldered mic from an amplified external mic I had using a plug removed from an old Zmodo cam. Guess is wrong impedience because I had to get very close to the mic to hear any resulting audio. I also removed and inspected the camera's built in mic. It is a light interference fit in the shell. I did forget to put a silica pack in it when I had it down. I have a donor bag from the old Zmodo that I'll probably put in it today.

Let me be clear. I still like this camera very much. Lots of features, beautiful image in all types of light and way faster than my 2 Huisun Mini PTZs. Where I have this camera mounted it will stay pretty dry and shaded. The audio for me was not the selling point. I would be interested to know if a firmware change would have effect but I haven't found anything of a later version. If someone could point me to that I would appreciate it. As you can tell, like a lot of folks on here, I am in a spend money to learn mode. It all started with a $35 640 x 480 Wifi Foscam. Graduated to Hikvision cams and now I think I am becoming a Dahua fan.

Thanks again for all the helpful comments. scguy