Plasma 6.0.1

With audio playing from laptop speakers, plugging in headphones results in
audio from neither the speakers nor the headphones. 

The audio volume widget shows 
Ports: 
1. Speakers (unavailable)
2. Headphones
Profiles:
1. Analog Stereo Duplex
2. Analog Stereo Output
3. Analog Stereo Input
4. Pro Audio

Profile 2 Analog Stereo Output is selected. Selecting the port "Headphones"
results in no change. 

After changing the audio volume by keyboard function keys or from the audio
widget, the headphone port can be selected, and audio plays through the
headphones. The Speakers port disappears.