On Mon, 12 Nov 2018 16:50:02 +0000,
lid (Adrian Tuddenham) wrote:

Can anyone suggest why this is occurring (bearing in mind that it only
affects the left channel) and can anyone suggest a cure?

I would guess(tm) that the "ticks" are coming from something outside
of the recorder. Try testing it again at a different location. If
the "ticks" go away, look around at your original location for
suitable culprit. Periodic noises are fairly easy, but random is
difficult. For example, I just found a similar problem that was
caused by RF noise from an ultrasonic mouse and rat repeller:
http://www.victorpest.com/store/rat-control/ultrasonics
The device produces random ultrasonic noises and whatever was doing
the randomizing was also producing random bursts of RF noise. You
might have something similar happening.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558