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Cordless earbuds are convenient.

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When earbuds get caught on something,

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they'll come flying out of your ears, but

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otherwise, they usually stay in your ears well enough.

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Even doing a spin is totally fine

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But if you keep spinning faster and faster...

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Eventually, your centrifugal force 
should be able to pull out your earbuds.

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So how fast would you have to spin
for your earbuds to fall out?

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Centrifugal force is determined by mrω²

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m = mass of an earbud
r = radius (earbud's distance from the axis)
ω = angular velocity

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First, measure the force required to remove the earbuds.

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I used this spring scale to measure it.

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Make sure that your earbuds'
tip covers are on correctly

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Pull straight

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It took 0.73 newtons to remove the earbud.
(plus or minus 0.007)

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So if we take one 5.4g earbud

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and gradually increase its weight...

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it should separate when it goes above 74g,
which is about the weight of a large egg.

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Now, let's make the person wearing these earbuds spin at high speed.

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Keep in mind, the axis of rotation is the
point directly between both earbuds.

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I made it a fixed axis so it won't wobble
no matter how fast he goes.

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I'm going to gradually increase
the rotations per second.

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The earbuds fell out after passing 6.5 rotations per second.

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At the point of exit, the earbuds were being
subjected to 13.8 Gs of force.

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Let's put this speed into perspective.

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Looking up the figure skater records for jumps,

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even Yuzuru Hanyu, who is going for the quadruple Axel, 
is said to have 5.71 revolutions per second.

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So even a Hanyu-level spin,
which you're looking at now,

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it's safe to say your earbuds 
probably won't come out.

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On the other hand, the glasses (20g)...

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started to shift at about 0.6N.

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Earphones fall out > Hanyu spin > Glasses slip off

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So, since spinning almost definitely won't
make your earbuds come out,

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all you have to worry about is them
getting caught on something.