Question Audio drift on NVR Dahua NVR4108-4KS2

[Sal992]

Hello, i'm new here. I have a small surveillance system: a Dahua nvr (NVR4108-4KS2) paired via cable with a little Imou Bullet ip cam. Whenewer i wish to export videos to my pc, i choose to save in mp4 i notice that audio, in the recording, tends to drift progressively. The longest the time extracted, the longest the delay (after 10 min almost 1 second shifted). Videos exported in DAV format are fine, instead. I would like to ask if anyone can provide any clue about this issue. Please, feel free to ask if more information about my setup is needed .

 

[Ralston18]

Update your post to include full system hardware specs and OS information.

What video software are you using? Is the software up to date?

Also, just for the record, if DAV is working what is the reason for using .mp4?

FYI:

https://www.winxdvd.com/resource/convert-dav-to-mp4.htm

Perhaps some proprietary related issue?

 

[Sal992]

Hi, thanks for the answer. Actually i am not using software of any kind: i forgot to mention that i am using Nvr's built-in feature to export files.
I tried 2 methods:
1- Backup on usb pendrive using the nvr OS;
2- Export directly on my pc, using web interface (browser Edge).
Sadly, i encountered the same indentical issue on both cases. Some months ago i tried also exporting in Dav and then converting in mp4, i think with WinX: same results.

Also, just for the record, if DAV is working what is the reason for using .mp4?

I agree, but my lawyer, wich recently required several hours of recording had some trouble managing Smart Play (Dahua's native app for *.DAV files which, by the way, works like charm XD) and she asked me if i can make the files VLC readable.
Usually i enjoy troubleshooting via google but at this moment i still have not found any similar issue recorded :| .
By the way, my PC specs:
Asus Rog Strix B555-f Motherboard
AMD Ryzen 7 3800 XT CPU
32gb (2x16)Corsair Vengeance ddr4 3600 RAM
EVGA 3070 XC3 Black GPU
Samsung 970 plus 1TB SSD NVME (plus secondary normal ssd and 2 1tb Hdd)
Corsair CS650M PSU
OS: Windows 10.
I will soon provide some info about encoding i'm utilizing on my nvr.
Edit:

https://imgur.com/a/IICDrh2

View: https://imgur.com/a/IICDrh2
<<-- Encoding info, Audio is set to AAC 16k.

 

[Ralston18]

What about the lawyer's PC specs?

What sort of troubles did she have?

 

[Sal992]

What about the lawyer's PC specs?

What sort of troubles did she have?

She uses a Hp (2017 maybe, looks like a cheap 250 g5) laptop, with hdd and perhaps only 4gb ram: i did not inquire very much about her problem, but i think it may be related to slow responsiveness while reading the files, due to low read speeds.

 

[Ralston18]

FYI:

https://www.ghacks.net/2022/03/08/v...t-with-fixes-and-support-for-dav-and-dts-lbr/

The question becomes, as you have noted, whether or not her HP laptop is up to the task.

Any chance the laptop can be upgraded: more RAM perhaps?

 

[Sal992]

he question becomes, as you have noted, whether or not her HP laptop is up to the task.

Any chance the laptop can be upgraded: more RAM perhaps?

Yup, i'm sure her laptop performance will skyrocket with ssd upgrade only (as i already suggested her). I checked a similar notebook for a friend, some years ago: it had some heavy bottleneck related to hdd high usage (100% almost all the time), solved with cheap San Disk ssd. I can only assume she did not upgraded it yet due to time-work related issues (not to mention sensitive information she has to backup first). Piece of cake for us, but not a task for a person with very basic informatic knowledge. Anyway, i really had not thought abut making VLC (wich works fine) Dav compatible. I think i'll give it a try!
EDIT: UPDATE
I tried VLC 3.017 Vetinari and omg, it works!! Time index bar selection by clik does not work, but video can be fast forwarded with no issue except it's a little choppy and some graphical artifacts tend to appear, only to vanish one or two seconds later .

 

[Sal992]

Update 31/05/22
I contacted customer service via Amazon, specifically the seller. I performed a complete reset to stock settings as they suggested. It is, in fact, a step i missed, because i used to copy and restore my old backup nvr configuration after cleaning it (usually once every 3-4 months). The problem seems solved, so i think it may be something related to "wrong" encoding options. I will try to replicate the issue sooner or later, i'm too curious .
I was also informed by my lawyer that she purchased a new laptop (it's about time XD).