There seems to be an inherent sociality of computers which is somehow related to their interactivity. However, existing research on this topic is limited to direct interaction, semantic information, clear goals and the visual modality. The present work replicates and extends a previous study on human politeness toward computer systems using a different interaction paradigm involving indirect remote sensors in the context of expressive musical performance with a guitar. Results suggest that the quality of interactivity of a system contributes to its sociality, demonstrating the relevance of an existing body of literature on social responses to technology to the aesthetic of abstract, expressive systems such as video games, artistic tools, ambient systems, media art installations, and mobile device applications. Secondary findings suggest the possibility of manipulating the inherent social presence of an interface through informed design decisions, but a direct investigation is needed on this issue.