UEA might not technically be RG, but it's still a strong university. Some of the stuffier law firms might recruit on a "RG or better" basis but they're increasingly in a minority, whats more important is getting a solid 2.1 or better from a good university, and UEA is a good university.
In truth for training contract applications the A levels will be the bigger barrier, BBD is relatively low when your competition will be typically AAB or better. Law is still a solid academic degree subject that gives plenty of scope for other graduate careers though outside of law.
As a final point - music law doesn't really exist as a discipline* although some firm's have strong media practices (Olswang did before it was absorbed by CMS). This would typically come under Intellectual Property (IP) law where some firms may serve clients in the music industry.
* - Ok there will be some music specialists out there but generally speaking it's a *tiny* niche in UK legal practice and not something you can elect to specialise in as a trainee or junior.