is it possible to change to one of my other gmail accounts and still access my Google Music from my primary gmail account?
Yes. You can have more than one google account associated with your phone at a time. Just go into accounts, add account, select google and sign in.
So if account a is associated to your Google music, you can just add account b to the phone. Then if you don't care about emails in account a, you can turn off the email sync for account a and turn it on for account b.
If you want to have account b as your primary phone account, you would have to factory reset your phone because you can't change the primary account while logged in. After factory reset, sign into your phone with account b, then add account a, when syncing google music, choose which one to sync.
Sent from my DROID RAZR using Xparent Purple Tapatalk