The speakers on my MacBook are not working.

There may a few reset sequences that could help alleviate symptoms you've noted.

• Reset NVRAM or PRAM on your Mac - Apple Support

https://support.apple.com/en-us/HT204063

Instructions above require a fair degree of timing, to hold 4-keys rather precisely

on startup/restart ~ and hold them down until sufficient time passed (you may

hear Mac 'chime' on restart) two or three Chimes are heard. Then let go of keys.

[You may have to repeat the sequence IF the Mac does not actually reset NVRAM.]

Another reset involves 'system management controller'. These Instructions evolved

over time. Mostly this appears (or acts like) a 'power management' reset, of a sort.

[This also uses a 'four-key' sequence.. Unlike previous 4; & different method, too.]

• How to reset the SMC of your Mac - Apple Support

https://support.apple.com/en-us/HT201295

The system management controller is responsible

for managing behaviors related to these features:

• Power, including the power button and power to the USB ports
• Battery and charging
• Fans and other thermal-management features
• Indicators or sensors such as status indicator lights (sleep status,

battery charging status, and others), the sudden motion sensor, the

ambient light sensor, and keyboard backlighting

• Behavior when opening and closing the lid of a notebook computer

Since power management can also affect the audio system in Mac

this reset could help. Also try Safe mode (re-start w/ shift key held)

until screen has you login & then, see 'Safe' mode words in screen.

[To exit, as blue-link instructions say, restart Mac normally.]

If these have been tried successfully a few times each, you could

choose to try and Get Support to have MacBook inspected & an

estimate of cost to fix whatever the cause, may be given.

Glad the "magic in the machine" was able to hear

of your instructions & then helped you, help itself!