You need to change placement of at least one of the subs. You can do a sub crawl or measure with one sub in a different place in your room.
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His "subs" are built into his speakers. They can only be moved by moving the speakers. Doing a sub-crawl will only be useful if he can place a speaker where the bass modules in the speakers work best.
spearfish25, you've encountered the problem with using "full-range" speakers... you need to place them where they need to be placed for imaging and soundstage... which is virtually NEVER the same place subwoofers need to go for bass response. This is why it's far preferable to use separate subwoofers that can be placed optimally for bass response.
Your *best* solution is to get separate subwoofers and then optimize their placements. That is a whole different discussion and is beyond the topic of this thread. However, if you go that route, visit the Subwoofer Forum for help with that.
Your second best option is to try adjusting the placements of your speakers. You're probably dealing with the length mode of your room, so try adjusting them along that axis. Move them closer to the wall behind them, or move them further out into the room, and see if you can impact the nulls caused by that mode. Just realize that everything you do to the speakers affects the response over the entire bandwidth f the speakers, so be sure you're not creating more problems than your solving by moving the speakers.