Ok will take a look at it and see.
I tested it and i dont get stuck on my end. it does its noise then stops I have upgraded multiple blocks to.
what were you doing when this occurred (just upgrading or refilling the fire traps or)
but its these 2 lines in items.xml that you can play with with the trapgun -
<property name="Repair_action_sound" value="Auger_Fire_Start"/>
<property name="Upgrade_action_sound" value="Auger_Reload"/>