I had a similar issue but it was related to the state of the battery rather than air temp. It ended when I replaced the battery ($25 or so). I would have tried cleaning the power/volume potentiometer first but it seemed like a hassle given the compact layout.
I have the same problem ( on three devices), after one year , it doesn't turn on without external power supply , either if the battery is fully charged. Maybe an electric capacitor ? if someboby can help us .....
1 
I had a similar issue but it was related to the state of the battery rather than air temp. It ended when I replaced the battery ($25 or so). I would have tried cleaning the power/volume potentiometer first but it seemed like a hassle given the compact layout.
由 Mike Licht 完成的
hello
I have the same problem ( on three devices), after one year , it doesn't turn on without external power supply , either if the battery is fully charged. Maybe an electric capacitor ? if someboby can help us .....
由 pascal 完成的