Angel harps for ever ringing rest not day nor night

This is the second line of the hymn by Francis Potts that begins "Angel voices ever singing round thy throne of light."

Robin pointed out the day before yesterday that although angel voices sing, it doesn't seem that harps ring. The bells in heaven ring, that's for sure. But do harps ring?

This hymn calls for some emendation. My proposal is "Angel harps for ever pinging..."

Annie says harps don't ping either, but I think they do.