It may be impossible for a little speaker to produce any sound at some low frequency, so manufacturers use "virtual pitch" psychoacoustic phenomenon by introducing harmonics above that frequency. There is no low bass, but there will be added harmonics that will be perceived by the listeners as low bass: https://sound.stackexchange.com/questions/37755/how-do-psych...
Here's also a project and some info from Asahi devs on Macbook audio:
https://github.com/AsahiLinux/asahi-audio