6 month old screams in Diono car seat

[Biotechick829]

Our 6 mo old has graduated onto a convertible car seat. We have two different brands, one for my car (Diono Radian) and one for my husband's car (Britax Advocate). She fusses at first in my husband's car but is then fine. When I put her in my car she screams bloody murder and cries the whole car ride. I have gotten a new car and moved her car seat from outboard to middle position, but would this be enough of a reason for her to freak out? I can't seem to see anywhere she would be uncomfortable (pinching, clothing bunching, etc) but I just can't seem to figure out what's going on.