DDJ SB3: speaker no sound (headphone does)

i know this topic has been discusses a lot online and i did my research as well but with no luck. so i really need to ask this again to make it work.

i just purchased ddj sb3 for practicing before going further to mixing on ableton push. after installing everything, there was just no sound. i did quite some research online about this topic and tried lots of things but there's still no sound coming out from speakers. 

so the volume display works fine, both on ddj and  serato. i did turn on master bottom, trims, changed the soundcard in macbook to ddj, i even bought another usb cable to replace the original one that came with ddj (since there are people talking about the problem of original cable), and the cable for my master output is currently with rca.

i do have sound coming from headphone, but not from speakers. sound works fine on serato, so i really dont know what the problem is anymore. 

the only things i can think of, from my limited knowledge, are the usb cable or speaker cable. as i said, i replaced the original usb cable with a new usb cable, hoowever, as i didnt manage to get a cable of type c (macbook) to type b 2.0 (ddj), i use a converter to convert it to type c. while i was using the original cable from pioneer, i used to wonder if it could be the problem of my converter (adopter), then the next minute i gave up this idea since the converter works fine with my ableton push to my macbook. 

then the second doubt i have is the cable of my speakers. i use presonus eric xt5, and the cable i use is a costumed 2ch multi cable. the cable is pretty new and the guy who made the cable is an expert, this is not the first time i bought cable from him so i doubt it would be the core problem.

anybody got any other idea? thanks in advance and much appreciates if anyone has second thoughts on the problem im facing.