Default Value?: Size of IPC buffer (in bytes) when streaming transcodes

I know there are a variety of debates on what this value should be. I want to know what the DEFAULT is. I’m having some issues with some local buffering on the same local wired network, and I wanted to rule out any custom settings I may have put in once upon a time.
So what’s the recommended default, and what values do the rest of you recommend and why?

Thanks!