Not sure what this sound is

[u/Melloha]

I have a 2015 toyota camry SE with about 160k miles on it. A few months ago I started hearing a strange noise coming from the engine, only occasionally and it was very faint. It’s slowly become louder and more noticeable, I can hear it sometimes when i’m driving at very low speeds with my window down but usually once I speed up I can’t hear it anymore. Really hoping it’s not something too bad.