all compression does is make the delay louder. Its still there but compressor just brings the volume up. The Feedback is the main key.. just becareful because sometimes like u said the volume jumps up. But on FL the delay has a volume out also. So u can control how much comes back and how much comes in.. I use Logic tape delay. and just keep the feedback below 50 otherwise ull get delay throught the Whole track and i wont stop until u lower the feedback down below 50.. Space dub delay its called.