Final answer:
Initially, check the speaker power, volume, and ensure the cable is connected to the correct audio output on the PC. Moving the cable to another jack can help diagnose if it's a port issue. This basic troubleshooting step is more straightforward than reinstalling drivers or replacing hardware.
Step-by-step explanation:
When a user complains that speakers are connected to a PC but not playing audio, the first step should be to check the most basic settings and connections before moving on to more complex troubleshooting. You should verify that the speakers are turned on and the volume is up both on the speakers themselves and on the computer. Next, check the speaker cable is properly connected to the correct audio output jack on the PC. If the speakers are known to work on another device, but not when connected to the PC, then consider moving the speaker cable to another jack on the sound card to rule out a port issue. This is usually a more immediate and simpler step to diagnose the problem as opposed to more technical procedures like reinstalling sound drivers or installing a new sound card, which may not be necessary if the issue is simply a bad connection or incorrect output selection.