I'm assuming your spi has three patches on it: The retrieval lines goes through the snuffer bag, out the snuffer ring, through the bottom and middle patch and is attached to the top patch.

When you pull on the retrieval line you end up pulling all three patches together through the snuffer ring, bunching up everything and making it hard to pull on.

The solution is to force the patches to be spaced out by a small amount, sufficient to avoid the bunch up. In my experience the snuffer ring on the stealth is big enough to let two patches going at once. I've tried to completely separate the three patches, but I found then that my snuffer bag was too short and a bit of sail was always sticking out.

Anyway, depending on the way the retrieval line attaches to the spi you have multiple solutions possible. I have two spi, one has nylon loops, the other one has small rings. I use a different technique on both.

For the ring version I use a long bowline knot on the top patch, the knot cannot go through the ring on the middle patch and as such creates some space between the top patch and the two below. This sufficient to prevent bunching, the two bottom patches are going in the snuffer at the same time and the top one follows.

On the loop version I tied a loop of dyneema to the middle loop, and thread the retrieval line through it. So when I pull on the retrieval line the top and bottom patches enter at the same time, and the middle patch, pulled by the dyneema loop, follows soon after.