Canadian music major here! My experience with law school admissions will not have been quite the same as those in the US who are trying for T-14 but I can share my two cents. GPA and LSAT are weighted more equally in Canada so I was not under as much pressure to get an amazing score on the LSAT. However, I did make it into the University of Toronto fairly early in the cycle, one of the most competitive schools in Canada, with an excellent GPA and an LSAT slightly below their median. I have seen plenty of people with LSAT scores well above mine on the Waitlisted/Rejected threads. Of course, I cannot know for sure, but I think my background as a musician was an asset in my application. I really leaned into the musician angle and discussed how I believed a performance degree left me uniquely prepared for the rigours of law school. Some examples being collaborative skills through things like chamber music and large ensembles, leadership skills through conducting, performing under pressure, dedication to your instrument, etc. If being a musician is the main part of your CV, it's better to utilize it and and make the best case you can for how the skills you have cultivated can serve you in the law profession.

Also, anecdotally I know multiple music majors who have gone through law school and said that it was less stressful than their music degree. Take it or leave it, but when you factor in academics with regular rehearsals, performances, and practice time, music school is a real juggling act. A music major sounds fluffy when you don't really understand what it entails, so make it clear in your applications.

Hope this helps!