"He sang and played bass at the same time."
"He played bass and sang at the same time."
(Substitute subject and instrument as needed.)
Linguistically I suspect there is no difference. By the commutative property, A + B == B + A. But there are implications here that affect the music.
The positioning of the terms implies a sort of priority - is the subject a singer who is playing bass, or a bass player who is also singing? In the former situation, you'll be more likely to have melodious vocal lines and simple bass lines or bass lines that follow the vocals. In the other, you'll more likely have more intricate bass lines, and vocals that follow the bass.