Quicksilver 3000 throttle problem

My boat was running good today and then all of the sudden I went to take off and it wouldn’t go but .5mph forward and backward. The throttle would go down past parallel both ways but no juice.
I have taken it apart but don’t know where to go from there. Should I replace cables? Put it back together and try again? I can’t find solutions anywhere online. Has anyone had the same problem? Thanks

Check the plastic barrels on cables have seen them split and cable sleeve will slide in barrel have it mostly on the barrel anchors at control box. flush mount boxes are a pain to remove by looking at picture it a Ranger will more than likely have to come out the front they are a booger bear.....OPTI

Thanks! I’m about to dive in when I get home in a minute. I’ll keep you updated. Hopefully it’s not too complicated and I can get it fixed.