Intermittent Audio Issue - Ubuntu 20.04

I recently installed Ubuntu 20.04 on my Toshiba Satellite-L740 laptop. I seem to lose audio periodically. At first I thought I hit something on the keyboard accidentally, but can now confirm it is a random occurrence with no input from me. I have tried toggling the mute/volume of the system but cannot recover the audio. When the audio is lost there is still audio activity shown on the VU meter from the source shown under the output device in sound settings. I also plugged in headphones and am able to hear audio in the headset. When unplugging headset the sound does not return to the speakers.
There was no issue with audio on the laptop prior to installing Ubuntu 20.04 (previously Windows 10). It seems to come back on it's own sometimes but then gets lost again. A reboot of the machine sometimes recovers the audio but sometimes not.

I would appreciate any help/troubleshooting steps you can provide.

Thank you,

Joe