1. Download the latest version of the mod here on GitHub.
2. Move the downloaded .vpk file into your steamapps\common\Team Fortress 2\tf\custom directory.
3. Enable Play a last hit sound when one of your attacks kills an enemy in the Advanced Options.
4. Select Default as the last hit sound.

If you have problems with the dropdown, you can use this console command:

tf_dingalingaling_last_effect "0"

First you should try resetting all sounds with this console command:

snd_restart

If there are any specific problems, please create a bug report on the issues tab.

It is recommended but totally optional to play these sounds at their normal pitch. For this you can either go in the Advanced Options again or use the console command below instead for more precision:

tf_dingaling_lasthit_pitchmindmg 100; tf_dingaling_lasthit_pitchmaxdmg 100

Here's the same command but for sounds on hit:

tf_dingaling_pitchmindmg 100; tf_dingaling_pitchmaxdmg 100

If you're up for it, you can play the same sounds on hit too, but be warned!

1. Enable Play a hit sound everytime you injure an enemy in the Advanced Options
2. Select Percussion as hit sound.

If you have problems with the dropdown, you can use this console command:

tf_dingalingaling_effect "3"