Hi Skyranger,
The 1090 indicator swaps to Amber if no 1090 signals have been received in the past (IIRC) 5 seconds, so switching between green and Amber is perfectly normal. If it goes red, however, that indicates a fault with the SDR or antenna.
The Voltage / Throttled ‘Warning’ indicates that at some point in the recent past you have had a power supply issue which has caused the Raspberry Pi to go under- voltage. Points to check are that your power supply can sustain a minimum of 5 volts even if drawing over 2 amps, that you are using the correct supplied JuicEBitz power lead or a ‘same type’ replacement, that connection between the lead and the paw is sound and not ‘loose’ and the same for the other USB end and that there are no breaks or damage to the cable (not always visible).
Regards
Peter