Windows 10: Laptop makes speed of audio recordings fluctuate

I was recording a duet for a song I had recently arranged for piano, and everything went well until I tried to sync the two parts I had recorded. When I put it into a video editing software, one of the two parts would sometimes be ahead of the other one, and sometimes behind. I checked the two parts against a metronome, and realized that although I had initially recorded the two parts with a metronome, the audio recorded by my laptop would slow down and speed up at random intervals. To further test this, I recorded a metronome ticking at 100 bpm, and played the recording on my laptop with the same metronome ticking the same bpm beside it. Turns out that my laptop skews the speed of recorded audio! Although it doesn't mess up the speed too much, a difference of half a millisecond between two duet parts makes my song sound like a drunk man banging on a piano. Have all my hours of work gone to waste, or do I still have hope?

:)

 

Wow and flutter?

"Variations in the speed of playback of a recorded signal resulting in pitch variations and distortions. Wow has to do with small speed variations resulting in a wobbling sound. Flutter deals primarily with quicker speed
fluctuations. Wow is a slower form of flutter. The two cause audible distortions in the reproduced signal."




Hello guys, I have noticed some effects similar to the above description.

It doesn't happen very often, but a few times it was quite noticeable.

The music player was running among Maps 3.

Could it be that when the phone CPU is under stress, audio playback can suffer "wow and flutter" like effect?

 

High DPC Latency with System Audio Through Audio Interface.

All of my system audio is running through the Focusrite Scarlett 18i20 USB 2.0 audio interface.

While running PreSonus Studio One v3.5 (Digital Audio Workstation software), and while playing back an existing mix, the audio plays back at a slow, fluctuating rate. At best the audio is playing at 90% normal speed with a high amount of popping and crackling.
At worst, that audio is playing around 50% normal speed with an extreme amount of digital artifacting, and the audio sounds smeared and unlistenable. The CPU performance meter in Studio One reports an overload state, while the Windows Task Manager reports
only 14% CPU usage. Studio One also reports the latency from my interface as 42.7 ms. There was nothing else running, aside from the normal background processes from other applications I have installed, at the time of the test.

Outside of Studio One, other system audio from web browsers and games exhibits pops and cracks to a lesser degree, but are still significant. However there is no fluctuation of playback speed, in this case.

LatencyMon reports that USBPORT.SYS, ndis.sys, nvldddmkm.sys, and dxgkrnl.sys all exhibit overly long execution times (these are the top four listed in the Drivers tab, sorted by highest execution time). USBPORT.SYS had a maximum execution time of 17648.650833
µs.

Here's is the link to my Windows Performance Recorder results. I followed the instructions in the appropriate Wiki on this.

Google Drive : avertissement relatif à l'analyse antivirus

Hope you all can help me out! Go Internet!

 

It's possible the laptop had lagged when recording and recorded the notes at slightly incorrect intervals as it was thinking more at certain points than others. This is potentially fixable in the software (was the audio recorded to a MIDI file? or just an audio codec like mp3). It's also possible that the video editor is playing back in a lagged manner.

 

My laptop seems to record wrong every time, though. As I mentioned, I did several tests, and the audio came out wonky every time. Could it be possible that it is because it was a video (mp4) file?

 

You could try a program specifically intended for recording audio. I use CyberLink's Audio Director 7, available as standalone product or part of CyberLink's Director Suite:




A trial version is also available.

As it happens, Shareware On Sale has the previous version Audio Director 6 available for free today. Checking the offer just now it's still there, offer ends in about 8 and a half hours at 8 AM Friday UTC, 9 AM Friday CET, 3 AM EST, midnight PST: Free CyberLink AudioDirector 6 (100% discount) - SharewareOnSale

Notice that the Shareware On Sale free version is the Lite Edition, somewhat stripped down.

 

W10 constantly "thrashes" the CPU on my real and virtual setups (Apps?, Data Mining?, Telemetry?).
It's possible the thrashing is causing the delays.

You could try:

• Closing/disabling/suspending any other running software
• Increasing the Priority of the recording software

 

StupidDogEater

Suggestion: Look at Kari's My System Specs and fill in yours, might help provide more insight to the problem. Also check his solution for cooling of a Notebook/Laptop, any additional cooling can cause better stabilization.

 

I've had a used laptop that would do that, just the slowing down part. Made me give up a lot of work writing a program to record pen strokes. If all fails, get an external USB sound card see if it helps.