If you are clipping, changing to 24 bit won't help. But if you are not exceeding 0 db (i.e. not in the red) while recording, then you aren't clipping at the input stage. However, if you have your mains cranked up, you could be clipping at the output stage (when the digital audio is converted to sounds).
What do your waveforms look like? Are they going above 0 db?
