Maniq, spoken by 250–300 people in southern Thailand, is an undocumented geographical outlier of the Aslian branch of Austroasiatic. Isolated from other Aslian varieties and exposed only to Southern Thai, this northernmost member of the group has long experienced a contact situation which is unique in the Aslian context. Aslian is otherwise mostly under influence from Malay, and exhibits typological characteristics untypical of other Austroasiatic and Mainland Southeast Asian languages. In this paper we pursue an initial investigation of the contrastive strategies of the Maniq sound system. We show that Maniq phonology is manifestly Aslian, and displays only minor influence from Thai. For example, Maniq has not developed tone, register, or undergone changes typically associated with tonogenesis. However, it departs from mainstream Aslian phonology by allowing extreme levels of variation in the realisation of consonants, which in our view are best explained by its distinctive social ecology and geographical isolation.