D9200 showing 50-55Hz at 15KHz resolutions?

[PhoneGuy]

I haven't updated my cabinet for awhile. World Class bowling sound had began to stutter more with each update.  I went from .122 to .135 this week with even more stutter.

I have an ArcadeVGA and a D9200.  The PC is now old, an Athlon 1.5ghz.
I started looking at the refresh rates other settings that I have seen suggestions about for compensating for sound issues since sound was locked to video timing.

The D9200 menu screen shows 31.2 KHz/60Hz at when the PC is at 640x480
When I drop to the low resolutions
I see 15.4KHz/50Hz for wcbowl. Mame debug says it's using mode 384x288@60hz
I see 15.6KHz/50Hz for pacman. Mame degug says it's using mode 352x288@60hz

The D9200 shows low 50Hz values for any of the low resolutions I select with Quickres.

Are these values the D9200 is showing correct or do I have something setup wrong with the monitor, ArcadeVga, or the PC?

[Ummon]

You have to understand how your hardware (or software, in the case of soft15khz) works. That's a hint that the refresh rates you're seeing, and your sound stutters are probably not related. You just need a new PC to run newer MAME.

[PhoneGuy]

After reviewing the ArcadeVGA documents I realized that I was looking only at resolutions that would run at less than 60Hz. I checked some of the other modes and they showed 60Hz.  I turned off rotation for pacman saw that the D9200 showed 60HZ when mame reported it was selecting 288x352@60Hz.

Mame says wcbowl is only running at ~93% and that the sound buffer is having a number of overruns.  So it's probably time for a new PC or to revert to an older version of mame.