For speedruns (seen from the zsr rules in the leaderboards) you can only use the standard pj64 plugins, that being the default plugin that comes with the emu.
I use the standard Pj64 1.7 plugin and it works fine, keep in mind that pause buffering lag is completely different from Wii VC pause lag, not sure if that's the problem you're having with the pause buffering though, but pause buffering on emu is not that great hahah