Try checking 88.2, and changing the CD output to the 44.1/88.2/176.4. Start playing a CD with the volume very low. If your receiver doesn't support 88.2 you'll get a burst of noise. Heck, for that matter try 176.4 too, just remember to be careful. I don't like the non-integer upsampling to 48 kHz.
The bitmapping settings make very subtle changes in the audio. I believe it has to do with the noise shaping of the oversampling. I think I like #3 the most, but it's really hard to judge because of the amount of time it takes to change between them. #3 is supposed to be the most computationally expensive, and while other Sony CD/SACD players offered bitmapping methods 1 & 2, only the PS3 has enough CPU power to perform what ever is being done for the third.
