I wonder if this affects Australian models as well. I bought one less than 12 months ago. We also have a 240v power supply so maybe the circuit is the same.
I don't use the vibrato and I don't have the foot pedal connected at the moment.
I'll plug it in tomorrow and see if I hear any popping noises - if that is supposedly the problem. I do play through the vibrato channel because I use a small amount of reverb.