Possible Clues:

• Sailors' song
• Traditional sailors' song
• 'A home on the rolling deep in song of old (3,6)'
• Watershed for a traditional song?
• The sort of cottage on the coast for singing
• A certain air apparent in main dwelling
• Somewhere musical to live on the ocean?
• Waterhouse for song
• Where one might be at home, by the sound of such, on 4 down
• Traditional song of sailors