Controllers are causing stuttering and lag

I've been playing 2 player games with a few friends- namely Mario Kart 64 and Mario Party, and i've noticed that the game is all of a sudden stopping dead every few seconds for just a fraction of a second and sometimes longer.

I noticed it was worse with 2 controllers although with one it was present but barely noticeable. To test that idea, we tried trading off and using only one controller at a time and the freezing was the same as 1 player games. I tried letting mario party run with only com players and there was no lag. So, it's something to do with the controller or the plugin, but I don't know what to do about it.

Here's my specs:
Athlon XP1800
256mb DDR
Radeon 64DDR VIVO
Sound Blaster Live! Value
Thrustmaster Firestorm Digital 2 (12-button gamepad, no stick)
Windows XP Pro, SP1 (yeah i know, but it's good at other stuff)
PJ64 1.5 final
N-Rage's Direct Input 8 v2 1.81a
Jabo's D3D6 1.5
Jabo's Direct Sound 1.5

I configured everything for each game according to the Game-FAQ in the help, and for some reason many games aren't affected, such as Duke Nukem: Zero Hour.

Oh by the way, all the games are only running about 80% full speed or so, there's not a frame-skipper like in the SNES emu days is there? (not really expecting there to be, but might as well ask while i'm here)

Yeah, switching plugins fixed the problem, thanks. Too bad Mario Party doesn't work right with 1.4; it's the main game we play.
Sure hope Jabo is working on a 1.6.

I'm sorry, jack, but we can't all be a born-genius like you. If you really want to be a help, you can start giving out usefull information rather than screaming at everyone like a 10 year old kid for no reason. If you could just pull your thumb out of your ass for a few minutes and think, you would realize that you just make yourself look pretty sad when you find a question that's already been answered for 2 days and then add your own completely pointless and ignorant rant.
So for the record, jack, I think you would do better to spend some time out in real life where acting like you have been would get you dismembered. I've heard the term "one brick short of a load" and, well, you must be that brick.

Got to admit, if you were an author thinking about working on Pj64 1.6 or D3D 1.6, wouldn't you do it secretly to avoid spam?

No, I don't really expect a new one, but you never know. The bug in 1.5 that causes the lag hasn't been affecting me since I messed up a video driver update though, so I've been using 1.5 problem-free for a few days and I'm pretty well happy with the way everything's running; PJ64 is pretty impressive work for only having a handful of releases.