Radio Problem

[fuzzy6988]

Took off from uncontrolled (A/G manned) aerodrome X and had no issues with the radio (readability 5!).
Flew near controlled aerodrome Y's area and requested transit to get to the other side of the zone.
Got given an initial heading which I flew and then it went quiet...

Several minutes later I suspected there might have been an issue with the radio.
I started looking at my panel and then I heard:
"G-XX I've been trying to call you four times". I replied with "We just heard you once".

I look at my COM1 radio squelch and it was turned right down to the bottom.
Therefore I could not hear some radio transmissions.

I readjusted the squelch and the flight continued without incident.
I also readjusted the intercom (pilot-passenger comms) squelch to get rid of that hissing noise.

[Keef]

I work on the assumption the last person to fly will have tinkered with the radio, so preflight checks include "gain set, squelch on threshold". It avoids that embarrassment.