Monster Footstep Frequency

So I have a monster and I want to add a sound effect. I have a nice giant footstep (1.25s audio). So here is my design and I have many ideas but I don't know which one would be the best.

So my design is if the monster is not chasing me, there will be the footstep sound every 1 sec (So you would hear theoretically 2 sounds at the same time for .25s). Now if the monster is chasing you, the footstep sound would be every 0.5s interval.

My first solution is I add on runtime a audio source on the monster and play the sound. Once the sound finished playing, I delete the audio source.

Second solution is to add 3 audio sources on the monster and recycle the audio source if one of them is done playing.

Is one of the solution better or there is a better solution?

 

Not sure which is better, but there's no need to delete the Audio Source. It can always be there. Setting the Audio Source's clip to null will do what you want (save on audio memory)?

 

If I don't delete the Audio Source, the game's fps goes down. So I need to clean the Audio Source.