It sounds like the antinodes happen to correspond to your listening position.
You can try moving the sub a few feet at a time to see how that changes things. Another suggestion I've seen is to move the sub to your normal listening position (which implies movingn some furniture to make room) and then wander around the room looking for the best response. Move the sub to that location.
You can try moving the sub a few feet at a time to see how that changes things. Another suggestion I've seen is to move the sub to your normal listening position (which implies movingn some furniture to make room) and then wander around the room looking for the best response. Move the sub to that location.