I have uploaded an audio recording the URL to it is at the bottom of this post.
I have noticed other people with the same issue theres a couple of videos of people trying to show it but it's not really something you can see it's just the spongey feeling and this nasty creaking sound you get after hearing the click most noticeable if you press the RMB slowly.
Audio recording:
https://storage.googleapis.com/rockettsharex/ShareX/2020/06/viper ultimate rmb click.mp3
edit:
Not my video but someone created a video here that shows it quite well: