LOS ANGELES -- A judge has ordered a deeper review of Chris Brown's probation amid questions about his travel and how many community service hours he has completed.

Los Angeles Superior Court Judge Patricia Schnegg says authorities have raised concerns about the R&B singer's community service, his travel and a drug test administered in Virginia that showed the singer tested positive for marijuana.

She said at a hearing Monday that Brown has a medicinal marijuana card from California, but she urged him to consider how the public and his young fans perceive his actions.

The R&B singer remains on probation for the February 2009 beating of then-girlfriend Rihanna.