So when I plug my effects into my effects loop on my Valveking 112, it sounds like total garbage. A muffled unclear sound comes out. It only works when I plug my guitar directly into my effect pedals then into the first input. I dont change the order of the pedals or anything, what can be the possible problems?
are you pluging your guitar in the amps input and then taking all your effects from the effect out and in the return? If so, maybe your cables are broken or something...
Also, what effects are you putting in the loop?

Modulation effects are generally meant for the loop such as chorus, phaser, flanger, tremolo, delay.
Overdrive, distortion, fuzz etc are meant for the effect chain.

If you're mixing the wrong kinds of effects, that could be your problem.
yeah, don't put distortion/drive/gain/boost pedals in effects loop. i have a valveking 112 and i put everything except wah and my ds1 in the effects chain. try checking for dead batteries in your pedals or for bad wires