Fix audio dropouts

Sound cutting out for a split second, like a skipping CD? fix.fm finds each gap and fills in the short ones. Free, in your browser, nothing uploaded.

Updated October 22, 2026

FX-18 / DropoutsREADY

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In short

A dropout is a split second where the sound cuts out to total silence and carries on, like a skipping CD. A pause fades with the room; a dropout stops dead and clicks. Buffer underruns, USB and Bluetooth glitches and dropped call packets cause it. fix.fm finds each gap and fills those up to 10 ms from the sound either side. On our sample all 4 gaps went and 3 clicks went to 0.

What's happening

A dropout is a split second where the sound stops dead and comes back, like a skipping CD. The recording lost a few blocks of audio: an interface that couldn't keep up, a Bluetooth mic dropping out or a call breaking up. The gap holds digital silence, exact zeros.

That's different from a pause. A pause still holds a faint room hiss, and the voice fades into it. A dropout cuts mid-word, so each edge clicks.

fix.fm counts gaps of 3 ms to a second with sound on both sides. One is mild, three moderate, ten or one over 200 ms severe. Gaps up to 10 ms are filled in from the sound either side. Longer ones get soft edges, but the missing sound can't be invented.

In Audacity, select a gap of 128 samples or fewer and use Effect, Noise Removal and Repair, Repair.

FX-18 / Dropouts sample0:10

The dropouts sample. Four tiny gaps of silence, 4 to 10 ms long, sit in the middle of words, too short to see at this size but easy to hear.

How far the dropout fix goes

A voice with 4 gaps of 4 to 10 ms read moderate and after the fix fine, with no clicks left and the fill 1.1 dB closer to the real speech than silence. In music the fill came 15.6 dB closer. Gaps of 40 and 150 ms were too long to fill; their edges were softened from +9.6 dB to 0 dB and still reported. Measured on November 5, 2026 with the samples described in how we test.

The dropout fix looks for one thing: moments where the sound drops to digital silence for a few milliseconds and then carries on. The cases below are a clean reading and a piece of synthesised music with gaps cut in by software, so we know exactly what was in each gap and can check how close the fill comes.

FX-18 / How far the dropout fix goes7 clips

One clean reading and one piece of synthesised music, with gaps of digital silence cut in by software, then run through this page's fixer at full amount. Every clip plays at the clean recording's volume, matched to -23 LUFS, so the gaps are all that differs. Headphones help.

Clean reading

The reference. Nothing missing.

Voice, short dropouts

Four tiny gaps in the middle of words. Each one is a little tick, like a skipping CD.

Voice, after the fix

The ticks are gone and the words run on smoothly.

Music, short dropouts

Four gaps in held chords. Each one is a sharp tick in a sound that should be smooth.

Music, after the fix

The chords hold steady. The gaps are filled with the sound that was most likely there.

Voice, gaps too long to fill

A 40 ms and a 150 ms hole. The sound stops dead and starts again with a hard edge.

Voice, long gaps after the fix

The holes are still there, because nothing can invent that much missing speech. The edges fade instead of stopping dead.

Public-domain LibriVox voice and music synthesised by fix.fm. The gaps are cut in software rather than by a real glitch. So the clean version really is what was there before.

Measured on the fixer's output at full amount
Case	The check	Jump at the edges	Clicks	Left of the gap
Voice, short dropouts	4 gaps, moderate to 0 gaps, fine	+21.9 dB to -1.8 dB	3 to 0	-1.1 dB
Music, short dropouts	4 gaps, moderate to 0 gaps, fine	+32.5 dB to -1.6 dB	2 to 0	-15.6 dB
Voice, gaps too long to fill	2 gaps, mild to 2 gaps, mild	+9.6 dB to 0 dB	0 to 0	not filled

The check counts gaps where every channel drops to digital silence for 3 ms to a second, with sound on both sides. Its warnings start at 1, 3 and 10 gaps, or any gap of 200 ms or more. Jump at the edges is how much more sharply the sound changes direction at a gap edge than the clean recording does there: 0 dB or below is no sharper than the sound itself. Clicks are the ones the click check hears at the gap edges that the clean recording doesn't have. Left of the gap is the difference from the clean recording inside the gaps, against leaving them silent: 0 dB is no better than silence, lower is closer.

In the voice, each gap jumped +21.9 dB harder than the voice ever does, and the click check heard 3 of them. After the fix the check finds no gaps, no clicks are left, and the edges are no sharper than the voice. The fill comes 1.1 dB closer to what was really said than silence would. That's modest: speech changes fast, and a few milliseconds of a consonant can't be fully guessed. But the tick is what you hear, and the tick is gone.

Music holds its notes, so it can be guessed much better. Its fill comes 15.6 dB closer than silence, and the 2 clicks the check heard are gone.

The 40 ms and 150 ms gaps are over the 10 ms the fix will fill, so it only softens their edges: the sound fades out over a few milliseconds instead of stopping dead. The jump goes from +9.6 dB to 0 dB, and the check still reports 2 gaps, mild, because the sound in them is still missing. Record that part again, or cut around it in the audio editor.

AMOUNT blends the fill with the silence that was there. Everything outside the gaps comes back sample for sample, and a file with no gaps isn't touched at all.

What this does not prove: these gaps are cut in by software, so each one is clean digital silence with the sound intact either side. A real glitch can also leave a burst of noise, a repeated scrap of sound or a gap that isn't quite silent, and the check only finds true silence. How we test has the pass marks behind the check.

How it works here

01
Finds each gap
It looks for moments where every channel drops to digital silence and comes straight back, with sound on both sides. Pauses, fades and edits don't count.
02
Fills in the short ones
A gap up to 10 ms is rebuilt from the sound just before and after it. A longer gap gets soft edges so it stops clicking, and nothing outside the gaps changes.
03
Stays on your computer
Your file is never uploaded. The dropout fix runs in this browser tab.

Questions

What's the difference between a dropout and a pause?

A pause still has sound in it: a faint hiss from the room, the mic and the preamp, and the voice fades into it. A dropout is exact digital silence that cuts in mid-word and stops just as suddenly, so it clicks at both ends. fix.fm only counts gaps of that true silence, between 3 ms and a second long, with sound right before and after.

What causes audio dropouts?

Something in the chain couldn't keep up and lost a few blocks of audio. Common causes are a computer or interface with too small a buffer, a busy USB hub, a Bluetooth mic or headset losing its link, a call or video meeting breaking up, and a slow or full memory card. Next time, raise the buffer size in your recording app, use a wired mic, close other apps and record to a fast drive.

Can a long dropout be fixed?

Not by filling it in. Past about 10 ms there's too much missing to guess, so fix.fm only softens the edges so they stop clicking. Record that part again, or cut the gap out in the audio editor and join the sound either side.

How do I fix dropouts in Audacity?

Zoom in until you can see the flat line, select just the gap, then choose Effect, Noise Removal and Repair, Repair. Repair only works on a selection of 128 samples or fewer, about 3 ms at 44.1 kHz, so most dropouts are too long for it. fix.fm fills gaps up to 10 ms in one go and finds every gap for you.

Will the fix change the rest of my recording?

No. Only the samples inside each gap are written. Everything you can already hear stays exactly as it was, and a file with no dropouts comes back sample for sample.

Is my audio uploaded anywhere?

No. The file is read and fixed inside this browser tab and never leaves your computer.

Understand the next step

Cut around a gap too long to fill

Often turns up with Dropouts

Working on a song? Fix music checks it for this and every other problem a mix can have, in one pass.