In certain cases, for example when using an external Mic, there could be a delay in the audio when watched in the social channels.
OBS (and other streaming software) can solve for this by adding delay at the encoding phase.
On the OBS Audio mixer, click the gear icon next you your audio source:

Select Advanced Audio Properties:

Add a negative offset to your audio source (500ms = 0.5 sec):

A negative offset will fix delayed audio issue.