Eleven Rack Playback Engine?

Hi I'm running Pro Tools 11.3.1 On my Mac OS 10.9.5. I'm using an Eleven Rack as my interface. The problem I'm having in pro tools is with the playback engines. I was able to record a few tracks and play them back fine using a guitar coming through the eleven rack playing through an eleven rack custom rig, but now if my playback engine is set to the Eleven rack, all my tracks are distorted and hard to hear. the only way I can make them clear again is if i switch my playback engine to Pro Tools aggregate I/O. But While in this Playback engine I can't select my Eleven rack inputs to record. I tried every buffer size, and played with all the I/O settings in the Pro tools playback engine trying to record. How can i get the audio clear with the Eleven rack set as my playback engine?