Garbled recording after 6 hours [SOLVED]

[geoldr]

Hi all

I record long international radio streams overnight to listen to later in the car.

Lately, Audacity has been giving me garbled data after the 6 hours recording mark. My recordings are usually about 8-9 hours, but for some reason now it's been getting corrupted after 6 hours.

My PC Specs are:
Core i5-4670k
16 GB RAM
Nvidia GTX 670
256GB SSD (70% free space)
3TB HDD (95% free space)

My motherboard has Realtek audio chip, and I am using their driver with the StereoMix to record PC audio.

I am not sure why it is getting corrupt. This did not happen in the past, and I am not sure what change would have caused this issue.

Any ideas?

[geoldr]

Just to add to this: I am using Windows 8.1 64 Bit, and Audacity 2.0.5. I see they just released a new version, I will try upgrading to that.

[steve]

If the issue occurs at a particular time of day (or night), check to see if your computer has any tasks scheduled to run at that time.
You could also try defragmenting your hard drive (that can take a while, so you will probably want to leave that running overnight).

[geoldr]

If the issue occurs at a particular time of day (or night), check to see if your computer has any tasks scheduled to run at that time.
You could also try defragmenting your hard drive (that can take a while, so you will probably want to leave that running overnight).

I'll take a look. I generally have tasks running at 3AM, and there is nothing going on around 6:30AM when I get up to take a look and it's still garbled. If I stop the recording and start it again, it's fine.

I took a look at the temp file storage, everything looks OK. It's about 10GB of data that is stored.

[Gale Andrews]

In what way are the recordings corrupted - dropouts?

If you made a test recording with another recorder using stereo mix, such as Windows Sound Recorder you may well find the same problem.

Does Windows WASAPI loopback have the same problem http://manual.audacityteam.org/o/man/tu ... ndows.html ?

Modern versions of Windows defragment themselves if the computer is left on and idle.


Gale

[steve]

Modern versions of Windows defragment themselves if the computer is left on and idle.

but many people turn off their computers when not using them, in which case Windows has little time to defragment the disk and the disk contents can become fragmented, which reduces the number of large contiguous spaces, making write access slow down as the drive has to work harder to find empty spaces.

[geoldr]

My recordings are saved to the default directory on the C drive, which is on my SSD.

There are no dropouts, it's just garbled. I can upload a sample.

[Gale Andrews]

My recordings are saved to the default directory on the C drive, which is on my SSD.

Well that makes defragmentation (almost) a non-issue.

There are no dropouts, it's just garbled. I can upload a sample.

Please do. See How to post an audio sample.

Does the stream always sound OK in the app you're listening in?

Gale

[geoldr]

Gale

Here is the file:

https://dl.dropboxusercontent.com/u/654 ... sample.wav

The stream sounds great in the web streamer, but for some reason something is happening with Audacity where it is getting garbled information.

[Gale Andrews]

Here is the file:

https://dl.dropboxusercontent.com/u/654 ... sample.wav

The stream sounds great in the web streamer, but for some reason something is happening with Audacity where it is getting garbled information.

There are no apparent silences in the waveform (where I looked) but it sounds like, repeatedly, some of the digital samples are not getting written.

I think you will probably need to go through everything here http://wiki.audacityteam.org/wiki/Manag ... nd_Drivers eliminating possibilities. It could be if you look in Windows Task Manager that you will see some process running at the time in question that is causing the computer to work hard enough that the recording is compromised. Check your DPC latency performance (see the bottom of that Wiki page).

You should also investigate whether updating your sound device drivers would help. You want to have the latest audio drivers for your computer model obtained from the web site of your computer manufacturer or motherboard manufacturer.

Have you tried out Windows WASAPI loopback instead of stereo mix?


Gale