I cannot reproduce your issue.
When Premiere is acting weird trash preferences by holding down shift+alt while opening Premiere.
Make a backup of presets first.
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Adobe Certified Expert Premiere Pro CS2/CS6/CC
Adobe Community Professional
Might want to install just the QT codec not the player.
If your footage is variable framerate Premiere cannot handle this.
Convert to constant framerate with Handbrake before bringing it into Premiere. https://handbrake.fr/
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Adobe Certified Expert Premiere Pro CS2/CS6/CC
Adobe Community Professional