Odd Mouse Wheel Problem

[Frank Jahnke]

I have an odd problem with my mouse wheel: I can use it to scroll down a
page, but it is very erratic scrolling up a page. This happens primarily
when X is in a 24bpp mode; if I reduce the video resolution in X to
16bpp, it works much, much better (though there is still an occasional
issue). This started happening about the time I transitioned from XFree
to X.org.

I am running moused, with a mouse type of "auto". Within X, I'm using
the "mouse" driver, protocol "auto" with device "/dev/sysmouse". Options
for 5 buttons and zAxisMapping of "4 5" are used, though turning this
off works in x.org now, and makes no difference. I use Xinerama on dual
monitors; TwinView seems to make no difference.

It happens with both a Matrox G450 (open source drivers) or an nVidia
FX1000 (nVidia drivers). The mouse itself is a Logitech MX700 (wireless)
attached through a PS/2 adapter to a Tyan MPX motherboard. Otherwise,
the mouse works well.

Any suggestions on how I can fix this would really be appreciated.

Frank