Input sound very low and lots of noise

Inspiron 14 5000.  This has dual mics but the input sound level (even if set to input level 100!) is very low and there is background noise.  Oddly a USB webcam with Microphone sounds the same but a Jabra USB headset seems to be OK.

Is there noise cancelling somewhere on the mic settings?  Is there some driver issue?  Both Windows and Dell updates are "up to date".