I think this doable but not 100%. I have the beat buddy plugged into a pair of studio monitors using stereo cables. I’d like to also plug my guitar interface into the the beat buddy using my guitar interface and bias fx software. All mixes is output to studio speakers. Any issues with this setup?
To answer I’d need some more info on cables you are planning to use and maybe some drawings 
BB has two mono inputs and two mono outputs + headphone stereo output 
I am using all TRS 1/4 cables going to my studio monitors from R and L output of BB. Works perfect. i have guitar interface with a splitter (2 - 1 males) TRS cable i used before this that single end plugged into the Spark Riff guitar interface and the two split cables plugged into the studio monitors for stereo. I assume i can plug the split side into the input side of BB and have both (BB and guitar interface) go to my studio monitors w/o issue. i can post a pic as well later on. thanks
The TRS cables from the BB to the monitors… it will work, but…
The BB output jacks are TS unbalanced and the ‘ring’ of the TRS plug essentially may make no connection to the BB’s audio signal. The TRS inputs of the monitors are likely ‘electronically balanced’ so the non-connected ring connection doesn’t matter, but could pickup some noise or other artifacts somewhere in the signal path. TS cables might be a better choice for this connection. If the monitors had a true transformer coupled balanced connection via the TRS cable it may not work or may yield a low signal input. Try both TRS and TS cables. A balanced connection will have about 6dB hotter signal than unbalanced. If the signal is the same for both cables the connection is unbalanced.
Not exactly clear on the your interface/splitter/cable question, but the inputs of the BB should pass the signal through OK. No explosions or smoke should result in giving this a try. Again, connections in the BB are unbalanced and TS cables would be my choice.
My mistake and typo. I am using ts cables to the micro controller presonus and trs from controller to speakers.
Thanks for the explanation
