My girlfriend and I have been hearing this chime randomly for a while, and we cannot figure out where it is coming from. I recorded it with OBS, but it does not appear on the Discord, browser, game, or microphone audio tracks, so it seems likely to be coming from a system notification or another nearby device. Does anyone recognize the sound or know what might be triggering it?
3 Answers
I get a very similar sound on my Mac when the Mail app wants me to sign back in to Gmail. Check phone, tablet, and computer notification settings, especially mail apps and anything connected to the same accounts.
It sounds like an iOS-style notification chime, possibly one used by Gmail or another app. Some apps share the same set of prerecorded alert sounds, so it may not be possible to identify the exact app just from the audio.
Another possibility is an older phone alert, such as a low-battery warning from an older flip phone or Android device. If there are any unused phones, tablets, or smart devices nearby, check whether one of them is waking up or reporting a low battery.

I have also heard that chime from unrelated apps, including a garage-control app, so it may be a generic mobile notification rather than a Gmail-specific sound.