The 16/44.1 .wav you get when you rip the red book audio CD is about 55 MB, but the 24/96 .aif is also about 55 MB? Are you sure you are burning 24bit/96kHz CD24s with the Alesis? Maybe you are burning 16/44.1 .aif files?

Also is .aif compressed at all? Because you are importing a 55 MB .wav, then exporting an 85 MB .wav? Maybe you are importing a 16/44.1 .wav and exporting a 16/96 .wav? Audacity will dither and truncate 24 > 16 but I don't know if it will bit expand from 16 > 24.

After you import the .aif, then export to .wav from Audacity, it is a 24/96 .wav? You can find out if it is 24/96 by right clicking > properties > summary.

FLAC Frontend will definitely not dither/truncate (convert 24 > 16) or downsample (96khz > 44.1kHz). All it does is compress losslessly.