"Angels playing instruments are common in English art, appearing in a range of contemporary works, including embroidered vestments, sculpture and illuminated manuscripts. Angels on horseback can be found on wall paintings and in earlier manuscripts, representing Christ's holy army as described in Revelation. However the Steeple Aston Cope is unique in its conflation of these two elements." English Medieval Embroidery: Opus Anglicanum.
I made a special trip to London yesterday to see the Opus Anglicanum exhibit at the V&A, and I'm so glad I did; if medieval embroidery is your thing, then go forthwith! I doubt you'll find queues stretching round the block, but in its own quiet* way this is an astonishing show. Photography is not permitted, hence the souvenir postcard showing a detail from the Steeple Aston Cope, one of the many highlights; the piece dates from 1330-40, and what you see there is believed to be the earliest English depiction of a lute.
*Quiet until we reached the later sections when rock music from the museum's own shop next door to the exhibition galleries seeped in to break the medieval spell - pity the angel couldn't have amped up his lute...