Catalyzes the hydrolytic ring cleavage of 2-oxepin-2(3H)-ylideneacetyl-CoA (oxepin-CoA) via the open-chain aldehyde intermediate to yield 3-oxo-5,6-dehydrosuberyl-CoA. The enzyme consists of a C-terminal (R)-specific enoyl-CoA hydratase domain (formerly MaoC) that cleaves the ring and produces the highly reactive 3-oxo-5,6-dehydrosuberyl-CoA semialdehyde and an N-terminal NADP-dependent aldehyde dehydrogenase domain that oxidizes the aldehyde to 3-oxo-5,6-dehydrosuberyl-CoA. Can also use crotonyl-CoA as substrate. 2-oxepin-2(3H)-ylideneacetyl-CoA + H2O = 3-oxo-5,6-dehydrosuberyl-CoA semialdehyde 3-oxo-5,6-dehydrosuberyl-CoA semialdehyde + H2O + NADP(+) = 3-oxo-5,6-didehydrosuberyl-CoA + 2 H(+) + NADPH Optimum pH is 8. Aromatic compound metabolism; phenylacetate degradation. Activated by cAMP receptor protein (CRP) and integration host factor (IHF). Inhibited by PaaX. Disruption causes the conversion of phenylacetate (PA) into 2-hydroxyphenylacetate (2-HPA). In the N-terminal section; belongs to the aldehyde dehydrogenase family.