This article reports on a qualitative study investigating the construct of regulation within the context of small music ensembles in Higher Music Education (HME). A multiple-case study approach is chosen to explore the socio-emotional interactions and students' regulatory processes when confronted with socio-emotional challenges. The study relates group-level video observations of three ensembles (classical (2); jazz/folk/rock) with students' self-reported experiences (n = 11). The data were qualitatively analysed using theory-informed thematic and interactional analyses. The results showed differences between the ensembles with respect to the challenges experienced. Furthermore, the cross-case analysis suggested that the quality of interaction (i.e., positive vs. negative) had a direct impact on the wellbeing of the groups' socio-emotional climate and shared regulation. Positive interaction not only increased music students' likelihood of enjoying ensemble work but also had an influence on shaping their collective-oriented strategy use and creative output. In contrast, prolonged negative interaction was linked to lower motivation and decreased collaborative effort among group members. The use of humour and shared references, such as recording labels, emerged as recurring strategies employed by students as socio-emotional tools that facilitated social regulation.