A cushion plunger is likely what they are calling the little rubber string catcher that comes back towards your string from your riser. When you release your string. The arrow flies, then immediately after your string it's a string suppressor or plunger. It's fairly new gadget. Mathews has them on some bows and so does Diamond. The Diamond Marquis has one standard with a "V" cut into it.
I wouldn't change your arrows. Something else must be wrong and I think it's my original suggestion about the vanes hitting the string.
I can try to find a pic of one for you.
And yes if your rest needed to be moved it would be moved left. But, IMHO that would likely be because someone didn't set your bow up properly to begin with at Bass Pro.
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