lm386 based amps often suffer from frustrating oscillation issues . if you head over to diy stomp boxs , you will find tons of info about placing capacitors at various spots , using a different input ( pin 2 and three are different ) grounding , all sorts of stuff . i have given up on that chip as many other have as well . stuff like ceramic caps , carbon resistors , literaly everything and anything effect them . there is a punch amp , it uses a 7053 chip , folks seem to feel it is a much much better chip , for many reasons . they arent as readily availible though and not as cheap , but ... i switched over and bought some for later . in the mean  time , i graduated to using class d amp boards made by sure electronics , and they are amazing . check out my youtube channel , i have a whole rig for a band i built , we jam at the woods . lm386 is a nice place to start but unfortunately they can be challenging . if you simply want to get a single amp going , good luck , you will surely pull it off , but if you wish to continue this , i would encourage you to look into the punch amp ... sorry i couldnt be of more help , i went and looked for about 20 minutes and could not find the proper thread where the pins i capped worked , there is a ton of info there on this problem though ! later , pt2 .