Multiple mouse clicks when deleting emails and only pressing left mouse button

[Sunny Fitz]

I have changed the mouse and slowed down the 8 bit buss
access speed on the motherboard, and when I delete the
excess emails uning the left mouse button, sometimes,
most of the time, two or more emails will disappear when
the left mouse button has only been pressed once.

Very bad,

Please help to resolve this issue.