It might be the same mixing, but a different mastering. On mastering it is completely usual to have extra compression/limiting, some light EQ and even extra "c

It might be the same mixing, but a different mastering. On mastering it is completely usual to have extra compression/limiting, some light EQ and even extra "color". It is supposed to be subtle, but that hasn't been the case for quite a while. Mastering is also when you get the final "bits" that go into a CD, so you need two different mastering sessions to get two different sounding CDs.