Hmm, you could check the valves, make sure they are adjusted correctly. Your putting 91 octane or whatever you have wherever you are right? You could check the fuel filter make sure thats not plugged up.

Your not low on oil are you? Is the vtec engaging properly? Are your plugs gapped properly? Are they the right heat level?

Thats about all I can think of right now. Are the flat RPM spots consistant? Where does it happen?