We study a micromaser model based on a solid-state setup with a double quantum dot coupled to a microwave cavity. This model relevant for description of existing experimental setups was used previously and predicted bistable photon emission.
Here we revisit the model with the focus on the bistability of the emission process and using a recently developed theory of quantum metastability we come to the conclusion that in fact it does not feature any bistable behavior. We analyze in detail the method of full counting statistics used for the prediction of the bistability applying it to a simple electronic model and identify a likely cause behind its failure, namely, the large ambiguity of the fitting procedure.