Originally Posted by
RangerNS
... Or the tower radios could have been. The tapes are what was spoken into the operators mic, not necessarily what was broadcast, not necessarily what was received by the A/C, and not necessarily what was received in the headphones of the crew.
What we are hearing are not ATC tapes, live recording made by others on that specific frequency. If a live ATC listener/receiver able to hear, so does a/c.
Question is did maintenance checked and found any issue with equipment. Very unlikely or they fixed in 90 minute. FAA/TSB report should tell.
Some posters on social media suggesting, crew are allowed to erase CVR, that would raise more questions.