@Tony Campos yeah this is a real concern and you're right to think about it carefully for a solar node.
The STM32WB07 at the core of the MultiNav Pro+ does have configurable TX power levels in firmware, but it doesn't do automatic closed-loop regulation based on supply voltage out of the box — it's not like a PMIC that backs off output power dynamically as VDD sags. So if your rail drops and the PA is set to a fixed power level that demands more current than your source can cleanly deliver, you can absolutely hit that spiral you're describing.
The practical fix here is to implement your own supervisory logic — monitor your supply rail (the STM32WB07 has an internal voltage reference and ADC you can use for this) and step down your TX power setting programmatically when you detect the rail sagging below a threshold, say 3.0V. The BLE stack lets you set TX power per-connection or before advertising, so you can drop from max output to something like -8 or -12 dBm during low-supply periods and recover when the rail comes back up. You lose some range during cloudy stretches but you keep the node alive, which is the right tradeoff for a remote sensor application.
Worth opening a thread in the Dev Hub or poking at the firmware repo on GitHub — there's source there that might give you a starting point for the ADC monitoring side of things. If you're hitting something specific in the implementation I'm happy to dig into it further.
