I recently got a Code 50. After a few weeks of using it and learning the my.Marshall website, I realized it did not have any of the newer firmware updates. I updated it with v. 1.47 and now I do not get any guitar sound. I get sound from my phone when it's connected via bluetooth. How can I install the previous version of firmware?

I tried using the foot peddle cable to see if it is a cable issue and strange things happened. I hear some strange music broadcast. Not sure if some neighboring device connected to my amp via bluetooth. Is there any way to turn bluetooth off and on?

I tried doing the factory reset and it does not reset the firmware. Is it supposed to reset the firmware with the factory reset function?

Thanks.

UPDATE: I got this resolved. It turned out to be an issue with the guitar.