I still think your amp dip switches are jacked --- at least from the picture you've posted. That sure as heck looks like you have them opposite of what you want. I think i can see the little white nub that sits atop the dip switch to make sliding it easier and it is opposite the dark shadow. It looks like the shadow is actually the dark space behind the dip switch inside the amp casing.
If this isn't the case then your pic is really difficult to make out - even blown up on my HDTV.
What I see in your pic is
If that's truly what they are then that is not what you want for bridged mono operation. I'm with bass addict, you might want to take a look a the dip switches visually to ensure it's not just a camera trick.
Also --- did you notice that the on switch is NOT always on the right side according to both the user manual instructions and the printed silk screen on the back of the amp. Unfortunately it's not simply right = on
I checked my dips and they match what I've advised ratm to use with the exception of 4-7 (cause I used the amp in stereo mode with a pair of subs - rather than bridged with a single) and 1 and 10 because I didn't use the clip limiter either. My EP4000 was used in a subwoofer meet at 2011 HuskerOmaha meet and so measured with an expensive REW setup, and then measured with my omnimic multiple times in my room and others.
My measurements in my room with my EP4000
HuskerOmaha's measurements in his room with my EP4000.
Thus I know for a fact that mine was playing without the low cut filter engaged on my EP4000.
There's a simple test you could do to ensure your amp is playing frequencies below the optional 30hz or 50hz low cuts as it should -- even without complex measuring equipment.
Use the attached 20hz test tone.
Play the tone, measure the output with your SPL meter, and then flip switch 3, measure SPL again. If it drops spl when the switch is flipped to the left, then you do indeed need the switch to the right.
20Hz.zip 334k .zip file