Imperfect sound on xMAME 0.97

Hi

I have OS4.1 update 1 installed and would like to know if someone could give some tips&tricks to get better results with Mame.The problem is that the sound stutters a lot and even when it is in general good without noise as I said it stutters or "jumps" a lot.I am using MAME 0.97 that was released aproximately when OS4 update#4 came out.

I like MAME very much is probably my favourite application.
And I have to say that when I press the F11 key during the emulation the framerate jumps from 76% to 83% or 100% a lot giving me the impression that this causes my sound problem.

I want to give a better performance for my MAME for wich in this version I have installed more than 2000 roms.

Is there a problem of the emulator or the operating system?

What can I do to give better sound and framerate stability to my MAME?

I refer to framerate stability as the frames not jumping constantly a lot as I said above on this post.

I know too that I have a lot of commodities and programs at the startup on my Workbench.Could this be the reason of my problem with MAME?

I don't have too much ideas about this but if someone could help me I would be very grateful.I want to comment that I want to show this emulator to some friends too.And last but not least I remember to have it running on update 4 with good sound or near it and with less problems than on OS4.1 update 1.

Any help will be really appreciated more than ever.

@MamePPCA1
I have the same problems on my sam 800mhz