I know about the footswitch , thanks. For the mustang v2 I've made my own switch. Just a simpel on/of switch , 2 meter electrical wire and a 6,5mm jack. That's all and it works. The gt40 doesn't have a effects loop , just like the v2. Thats also an issue. To solve that I could buy the gt100 but in that case I'm also paying for a bigger peace of wood with a bigger driver. I don't need that because I already got several big Amplifiers. I will only use it like a stomp box. Question: is it possible in the gt40 to use a stomp box more than ones in a preset?