New trouble keeps finding Famous Dex ... even when he's in court dealing with previous legal issues.
Law enforcement sources tell TMZ ... the rapper was at a hearing Thursday related to the 19 charges he was hit with in March -- including domestic violence and gun possession, to name just a couple -- and he pled not guilty to those charges.
However, we're told during the hearing it was revealed that Dex had allegedly violated a protective order put in place after one of the alleged domestic violence incidents from last October.
Our sources say the rapper was immediately taken into custody, and is currently being held on $200k bond.
As we've told you ... Dex's string of big-time legal problems began in November when a SWAT team showed up at his home, and he was named a suspect in a domestic violence case.
A few months later, he was arrested for gun possession during a traffic stop, and just days after that ... he was hit with the 19 charges.