There is new release or BIOS for XPS 13 9343 laptop. It did not fix repeating keystrokes problem for me, but I did learn a few things in the process of installing the firmware update.

Upgrading to BIOS A04

Download A04

go to download page

then apparently there are 2 ways to proceed

1. Put file into /boot/efi and reboot
2. make a USB stick.

Make a USB stick

• Download FreeDOS USB image. I picked 256M version.

• Use gparted to create fat32 partition on your usb

• Use (kinda buggy) Setup Disk Creator to create FAT32 boot from the downloaded ISO file

• Insert USB stick and reboot machine

• Press F2 when Dell logo showes up to get to setup mode

• In Boot options pick legacy and USB stick. Apply, Exit

• Boot the disk, type to boot freedos, pick 4th option (no drivers), and execute the firmware update command.

• Follow instructions

Unfortunatelly these steps did not save me from repeated keystrokes as I said.