ShtBox

What’s up guys, I’m new here and I’m not sure if I’m posting in the correct place but I’ve got a 2005 Silverado 1500 and recently it’s sounding like it’s misfiring but there are no codes showing up and it happens every one in a while, I took it to a shop they said there were random misfire codes but nothing to worry about, I had my cats stolen a few years ago and fell in love with the sound of the motor, but the shops telling me that putting a muffler back on it will fix my problems? I’m somewhat at a loss, I’m not super mechanically inclined but I would love some advice.