At startup, the Linux kernel sets the repeat rate to its maximal value. For most keyboards this is reasonable, but for some it means that you can hardly touch a key without getting three copies of the corresponding symbol. Use the program kbdrate(8) to change the repeat rate, or, if that doesn't help, edit or remove the section
! set the keyboard repeat rate to the max mov ax,#0x0305 xor bx,bx ! clear bx int 0x16
/usr/src/linux/[arch/i386/]boot/setup.S
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