Speaker not producing the right sound after a led strip was introduced
The tone() command is interrupt driven.

To get the tight timing needed by the LED strips interrupts are disabled while sending the data.

That means the tone() command stops while you're updating the LED strips and starts again afterwards.

The end result will be the sound is corrupted - maybe sounding like it's bubbly or underwater or just "rough".

The two basically can't work together and I'm not sure what to suggest to make them work together on a low-end MCU like the AVR.