Unless the shot requires that distance move the mic closer. It should be just above the frame line. If you need the headroom for the shot that forces you to go 5' from the talent then use a wireless system. If you get closer with the boom mic then you should consider a cardioid or hyper cardioid mic instead of a shotgun.
If you are five feet above your talking heads, the mic is most likely picking up sound off the ceiling.
I have also read discussions that carpeting is not always preferred in that it can isolate the talent too much creating a dead sound environment with no natural sounding reflections.
Certainly get closer (within 3 feet is a very general rule for maximum distance from talent’s mouth) and consider asking Ty for advice on the best mic for your application. He has links to files of tests he has run and is very generous with this type of info.
If you have a decent budget, consider hiring a pro to help balance your studio for sound acquisition.
Also consider uploading some sound samples for the pros to hear what you are talking about.
Can't tell from pics. Do you have space behind talent? Lots of reasons not to place them against the backdrop.
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