A Windows Defender bug is making VLC take 30 seconds to open an MP3 file

[Alfonso Maruccia]

The takeaway: A recent social spat highlights the conflicting priorities between Microsoft and open-source projects such as VLC. The universal media player is having issues dealing with MP3 audio files, and the most likely culprit is Redmond's end-point antivirus software.

Is VLC media player taking tens of seconds to load an MP3 file just because open-source software development is now in an embarrassing state? Jonathan Blow, designer of puzzle games Braid and The Witness, accused the VideoLAN team of doing a very bad job with VLC programming. The VideoLAN team eventually pushed back on the accusation, blaming Microsoft and Windows Defender instead.

In a recent social post, Blow said he was going to switch from VLC to Microsoft Media Player because the former took 33 seconds before playing an MP3 file. Blow's view is that open-source projects are inherently flawed, while a media player programmed by Microsoft – which has never been known for its expertise in the field to begin with – is now a better alternative to one of the most popular pieces of software on the planet.

According to recent figures provided by VideoLAN, VLC has been downloaded more than 6 billion times on Windows, Linux, Android, macOS, and everything in between. The tool supports six different CPU architectures and numerous hardware-accelerated GPUs, while also providing a lot of additional features like media conversion, recording, internet streaming, IPTV, and much more.

– Jonathan Blow (@Jonathan_Blow) August 12, 2026

As confirmed by VideoLAN, the particular issue experienced by Blow is likely related to a known bug in Microsoft Defender. Redmond's endpoint antimalware service is now routinely targeting the plugin cache in VLC's installation folder, putting the cache file in quarantine and causing the player to delay its normal loading times.

Reinstalling VLC or simply regenerating the plugin cache should solve the issue. "Calling open-source software embarrassing when it is a Windows update that broke it is quite disrespectful," VideoLAN said.

When it comes to false positives and annoying behaviors with legit third-party software, Microsoft Defender is often the first culprit you can safely blame. The VLC plugin cache bug is a well-known issue at this point, with users trying several different solutions to make Defender and VLC finally coexist in peace. Using different antivirus software like Bitdefender Antivirus Free is also a great way to make Defender issues disappear – something I can personally vouch for.

As some users pointed out, using a video player such as VLC to listen to MP3 files doesn't sound like the most sensible idea to begin with. Furthermore, switching to the "worst media player on the market" (Microsoft Media Player) instead of modern MP3 players such as Foobar2000 is definitely an "embarrassment."

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A Windows Defender bug is making VLC take 30 seconds to open an MP3 file

 

[GeoffreyA]

Would recommend MPC-HC. Runs faster than a mouse bolting for its hole and plays everything.

 

[Thatsdisgusting]

And what about DLNA/SMB playback stuttering?

 

[Axeia]

Would recommend MPC-HC. Runs faster than a mouse bolting for its hole and plays everything.

Or you can just whitelist the plugin.

I had to do the same with my mouse (Roccat Tyon) software. Without the whitelist entry for windows defender saving a profile to the mouse it took half a minute, with the entry it's instant.

Alternatively,
My favorite is PotPlayer. It's crazy configurable/customizable (perhaps even more so than VLC itself). The downside would be if you don't like something finding the right setting to change it amongst so many settings can be quite hard.

I found SMPlayer ages ago trying to find a MPC alternative for Linux, but it supports Windows and Mac as well. It's a lot like MPC including looking like it's ancient out of the box.
It's basically just a userfriendly shell around mplayer so it'll play just about anything.

Does MPC support automatically resuming where you last left off nowadays (persisting between restarting it or even the computer)? That's a feature I really like from SMPlayer/PotPlayer.

 

[Honest Abe]

Windowz sucks. I left years ago. Linux and MacOS are all I use these days. Everything M$ makes turns to

 

[GeoffreyA]

Or you can just whitelist the plugin.

I had to do the same with my mouse (Roccat Tyon) software. Without the whitelist entry for windows defender saving a profile to the mouse it took half a minute, with the entry it's instant.

Alternatively,
My favorite is PotPlayer. It's crazy configurable/customizable (perhaps even more so than VLC itself). The downside would be if you don't like something finding the right setting to change it amongst so many settings can be quite hard.

I found SMPlayer ages ago trying to find a MPC alternative for Linux, but it supports Windows and Mac as well. It's a lot like MPC including looking like it's ancient out of the box.
It's basically just a userfriendly shell around mplayer so it'll play just about anything.

Does MPC support automatically saving progress where you last left of nowadays (persisting between restarting it or even the computer)? That's a feature I really like from SMPlayer/PotPlayer.

I used to keep VLC on the computer but never used it. My whole life, it has been Media Player 6.4, a bit of MPC, and MPC-HC. In other words, I'm stuck on the old-school paradigm.

No. As far as I'm aware, MPC-HC cannot store progress. Admittedly, it's a feature I do find useful on Samsung's Android player, which, by the way, is excellent.

I've heard great things about PotPlayer. Did try it once.

Finally, I use AVG, so don't experience issues with Defender.

 

[Axeia]

I used to keep VLC on the computer but never used it. My whole life, it has been Media Player 6.4, a bit of MPC, and MPC-HC. In other words, I'm stuck on the old-school paradigm.

I started with VLC, ran into issues with certain (fan-made) anime subtitles trying to do fancy effects.
Different outline colors for different characters speaking, text scaling up as someone got louder, karaoke style highlighting during the intro/outro songs, text being placed over a sign in a scene.. they can get pretty wild and creative with them.

MPC-HC was recommended as the more reliable alternative at the time, stuck to that for a while. But it didn't work under Linux so I switched to SMPlayer. Ended up liking SMPlayer better than MPC, better UI customization at the time and the auto resume feature were winners in my book. So I switched to SMPlayer entirely, even on Windows.

Saw PotPlayer mentioned in some comments on another tech site and gave that a try under Windows and haven't looked bad. Does everything SMPlayer does and way way more, and it feels more like an actual Windows app (can tell SMPlayer is using cross platform Qt for the GUI).

 

[tomkaten]

Stupid Defender does the exact same thing to Double Commander. When I had it enabled, it would take DC 5-10 seconds to launch. A freaking file manager !!!

I've disabled it now and DC loads instantly. Every single time.

 

[Lionvibez]

The bug affects VLC on win 10 also.

And the workaround for now is just to clear the cache in vlc which works.

 

[GeoffreyA]

I started with VLC, ran into issues with certain (fan-made) anime subtitles trying to do fancy effects.
Different outline colors for different characters speaking, text scaling up as someone got louder, karaoke style highlighting during the intro/outro songs, text being placed over a sign in a scene.. they can get pretty wild and creative with them.

MPC-HC was recommended as the more reliable alternative at the time, stuck to that for a while. But it didn't work under Linux so I switched to SMPlayer. Ended up liking SMPlayer better than MPC, better UI customization at the time and the auto resume feature were winners in my book. So I switched to SMPlayer entirely, even on Windows.

Saw PotPlayer mentioned in some comments on another tech site and gave that a try under Windows and haven't looked bad. Does everything SMPlayer does and way way more, and it feels more like an actual Windows app (can tell SMPlayer is using cross platform Qt for the GUI).

All use the same subtitle rendering library today, libass, so the results should be similar. Mpv is another player of note; its spun-off tonemapping library, libplacebo, has been indispensable for converting 4K HDR movies to SDR, sometimes doing a better job than the official Blu-rays.

 

[axiomatic13]

All use the same subtitle rendering library today, libass, so the results should be similar. Mpv is another player of note; its spun-off tonemapping library, libplacebo, has been indispensable for converting 4K HDR movies to SDR, sometimes doing a better job than the official Blu-rays.

MPV is my favorite. The UI is perfectly undistracting from the media and the performance it stellar. All of my media is 4k HDR 10 bit.