Keyboard conflict in controller setup

[Foil]

Hey, all. I'd appreciate any suggestions on this, especially from anyone who's played me recently.

I use joy & keyboard, and I'm extremely comfortable with my current setup:
Joy (Cyborg Evo or 3D P-Pro): orientation/rotations, weapons
Keyboard:
Sliding - A, S, D, F
Forward/Back - CapsLock, LShift
Afterburner - Space
(Other stuff in sensible places which don't require me to move my fingers off their places.)

I consider it a fairly decent, relatively practical controller setup, except for one minor detail:

Since I bought my new machine (including the keyboard) there's apparently a conflict when I try to trichord/afterburn with a couple of particular combinations (Caps/A/S/Space and Caps/D/S/Space). Basically, the slide down (S) doesn't register.

It's not a huge deal, but it's thrown me off a couple of times, and once even caused me to suicide while making a flag-escape in Veins (a napalm I was throwing into the ceiling ahead of me - I didn't make it underneath ).

Any suggestions? I thought to move my keyboard hand (left) over to the right by a set of keys, but I think there are some similar conflicts there. I also prefer to use the keyboard instead of the hat for sliding, for various reasons.

Thanks for any help.

[Top Gun]

Your keyboard probably can't register more than three keypresses at once. It's a problem that affects most lower-end keyboards.

[WarAdvocat]

Yep!

Try swapping your old keyboard for your new one

[Foil]

I checked, and my old keyboard has the same issue.

Any suggestions on an affordable keyboard which wouldn't have the conflicts?

[WarAdvocat]

Key Tronic