The development of fast and lightweight systems for consumer electronics has the potential to improve the energy efficiency of digital audio. Hence, end-user applications become more affordable and thus in higher demand. Ultimately, the expected gains which were made possible by technological advancement are hampered by changes in modes of consumption. This is known in environmental economics as rebound effects. In this context, our article presents two case studies: plastic use in discs and cassettes during the late twentieth century and energy use in online streaming platforms since the 2010's. For the former, we find that resource consumption has grown even so per-unit audio coding efficiency has improved, because of a rise in demand and of the use of plastic in packaging. For the latter, the risk of rebound effect is real but the digital music industry is enacting a strategy of opaqueness which prevents precise estimations. Scientists of the "Internet of Sounds" must take action to involve sociopolitical factors in their impact assessment of digital audio.