Use relays. Instead of using onactivate, use onrelay for all of your events, and trigger the relay with an onactivate event.Then add onrelay > self > firerelay when you want to repeat it.
why do you want the sound of a door opening to repeat?
"EXAMPLE"
[ 0 ] onActivate > self > fireRelay[1000] onRelay > self > fireRelay[ 0 ] onRelay > self > playsoundOnce activated, the block will play the selected sound repeatedly every second.