“…The only clue comes from Zabala et al (2016:160), who state that the noise frequency of palato-alveolar /ʃ/ can change depending on the formants of the neighbouring vowels, referring to García Jurado (2005), according to whom /ʧi/ has an initial transition frequency of 2.146 Hz, while that of /ʧo/ is 1.735 Hz. Apart from this documentation of an expected coarticulation process, there are no indications in the phonetic descriptions of Argentine Spanish that coarticulatory labialization should be a prominent or inherent feature of /ʧ/ (or other fricatives) (Lipski 1994:168-172, Harris & Kaisse 1999, Baker & Wiltshire 2003, Hualde 2005, Chang 2008, Kochetov & Colantoni 2011, Colomá 2018). Further research is required to establish whether this is because /ʧ/ is not generally labialized, or whether labialization before rounded vowels is considered a natural process of coarticulation and therefore does not attract attention.…”