One of your devices does not have the correct driver installed.
Either your sound card, voice / speaker-phone modem, or other similar device has an improper / incompletely installed driver.
If device manager does not give you a clue as to which device it is, start with the last device that you installed.
Go to the manufactures web site. Look for either patches, or a newer version of the driver.
Follow their instructions for updating the driver.
You may have to remove the device from device manager,
shut down the system,
physically remove the device,
start the system,
install drivers,
shut down the system,
install the hardware,
start the system and complete the installation.