Backcourt violation?

[vawils]

Should be a simple answer to this situation but our pretty new crew had a discussion on this play. A1 has the ball in front court and passes to A2. The ball is tipped by B1 and then also by A2 in the front court and then goes into the backcourt where it is retrieved by A2. Is this a backcourt violation? Seems it should be but some confusion since B1 touched the ball but A2 also touched it in the front court last before it went to back court and no team control change.