This paper addresses one of the most contested issues in phonology: the derivation of phonological typology. I present a new model for deriving phonological typology within the Channel Bias approach. First, a new subdivision of natural processes is proposed: non-natural processes are divided into unmotivated and unnatural. The central topic of the paper is an unnatural alternation: post-nasal devoicing. I argue that in all reported cases, post-nasal devoicing does not derive from a single unnatural sound change (as claimed in some individual accounts of the data), but rather from a combination of three sound changes, each of which is natural and motivated. By showing that one of the rare cases of unnatural sound change reported actually arises through a combination of natural sound changes, we can maintain the long-held position that any single instance of sound change has to be natural. Based on several discussed cases, I propose a new diachronic model for explaining unnatural phenomena: the Blurring Process. Additionally, I provide a proof establishing the minimal sound changes required for an unmotivated/unnatural process to arise. The Blurring Process and Minimal Sound Change Requirement result in a model that probabilistically predicts typology within the Channel Bias approach. This paper also introduces the concept of Historical Probabilities of Alternations (Pχ) and presents a groundwork for their estimation called Bootstrapping Sound Changes. The ultimate goal of the new model is to quantify the influences of Channel Bias on phonological typology.