No sound on Macbook pro early 2015

Here are a few steps you can try to get your audio working again:

Basic Checks:

1. Volume and Mute: This might seem obvious, but double-check that the volume isn't muted and is turned up on your Mac. You can find the volume controls in the menu bar or through System Settings (or System Preferences) > Sound > Output. I do appreciate, though, that the problem appears on the Windows partition, too.
2. Output Device: Make sure the correct output device is selected in System Settings (or System Preferences) > Sound > Output. It should be set to "Internal Speakers" unless you have external speakers connected.
3. External Devices: Disconnect any external speakers or headphones that might be plugged in. Sometimes, a device can interfere with the internal sound.
4. Restart: A simple restart can often resolve temporary glitches. Give your Macbook Pro a reboot and see if the sound comes back.

Software Solutions:

1. Software Update: Make sure your macOS is up to date. Outdated software can sometimes cause sound issues. You can check for updates in System Settings (or System Preferences) > Software Update.
2. Reset Core Audio: Core Audio is the software that manages sound on your Mac. Resetting it can sometimes fix problems. Open Terminal (located in Applications > Utilities) and type the following command: sudo killall coreaudiod (press Enter and type your password when prompted).
3. Reset NVRAM and SMC: NVRAM and SMC are settings chips that can sometimes get corrupted. Resetting them can help resolve various hardware issues, including sound problems. Instructions on how to reset NVRAM and SMC can be found on Apple's Support website depending on your specific Macbook Pro model.

Further Troubleshooting:

If none of the above solutions work, then the problem might be hardware-related. Here are some additional options:

1. Apple Support: If you're comfortable, you can try troubleshooting further with Apple Support If the internal speakers on your Mac aren't working - Apple Support.
2. Apple Authorized Service Provider: If you're not comfortable troubleshooting yourself or the problem persists, you can take your Macbook Pro to an Apple Authorized Service Provider to diagnose the hardware issue.

Since your problem affects both the internal speakers and headphone jack, it's less likely to be an issue with the individual components themselves, and might point towards a deeper software or hardware problem.

Hopefully, one of these solutions will get your Macbook Pro's sound working again!

Generally on the older Macs, it is the headphone jack which can cause a problem preventing the internal speakers from working or being an option because the older headphone jack would have one of the spring metal contacts bend & short against the grounded side of the headphone jack making the laptop think headphones/speakers were connected. It is possible when inserting the headphones/speaker connector did not push the spring metal contact from shorting out.

I forget exactly when Apple changed the design of the headphone jack which eliminated this problem. On Macs with the headphone jack issue, you will see a red light in the headphone jack when playing audio. More than likely this is the problem you are experiencing. Sometimes it is possible to push the spring metal contact away from the grounded casing of the jack, but it is not easy to do.