Place it immediately after the question or failed guess, as the beat before the reaction lands. Follow it with Nope when the answer is a refusal, or with Okay Let's Go when the group decides to move on anyway. Keep it as a single reaction beat inside gaming and chat edits.
Über diesen Sound
This two-second clip is Deimos from Madness Project Nexus making a drawn-out, uncertain 'uhhh, uhmm' sound, with no other words or music. It feels awkward and funny, like someone caught without an answer and stalling for time. Taken from the game, it works as a quick reaction to hesitation, confusion, or a conversation that has suddenly gone quiet.