NR709 Audyssey volume issues

System setup: Panasonic P55ST30 Plasma, Onkyo TX-NR709, 1 pair Martin Logan Motion 12 mains, Xfinity HD DVR. Complete system purchased January 2012. Issue: I ran Audyssey calibration for 5 seating zones within living room. When watching TV, audible level stops increasing >60db, even though the visual volume continues to 100. In other words, between 60db and max volume, there is no difference in audio level or sound.
Is this an issue with my setup?
Limitations with Martin Logan speakers unable to disperse multiple audio projections >60db?
Firmware issues?
Hardware issues?
Also, once in a while my HDMI startup fails to initiate with Xfinity DVR (cable service).

In regards to your issue- it would possibly be more effective to contact our Product Support Dept for further assistance with this specific issue via our phone number and hours of operation below. We would like to speak with you and work to troubleshoot and resolve your issue, with you having access to your unit, as prompt as possible. We would like to speak with you and provide a thorough answer to your inquiry and assist you with any further questions you may have. You can reach Product Support at 800-229-1687 they are here from 9am to 8pm Mon. to Fri. and also Sat. and Sun. from 10am to 4pm eastern std. time.

Thanks,

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