8d Serpigo - 'pi(ous)' (very good, in) 'ser(e) (withered, short) go (crack; try)'
35a Spongebob - 'sponge' (cake) + 'bob' (old coin)
56a Sphinx - 'sp (latest) h(ard) in (fashionable) x (times; multiply)'
57a Remedies - 're + me' (notes; music) + 'dies'