The crew was obviously curious and maybe just a little weirded out by the eerie sounds coming in through their headsets, enough to mention it to each other. But none of the men was so concerned that he lost focus on the task at hand. The transcript shows their procedural conversation is peppered with a few mentions of the eerie sounds, but they also continued photographing craters on the Moon, checking their flight plan against the upcoming moment they would reacquire communications with Houston, and ate some brownies and grape juice. And Young quickly solves the mystery. He points out to his crew mates that it’s probably nothing more than radio interference between the two spacecraft, which is all that it was. Apollo 10 was the first mission to take two spacecraft each with a radio communication system to the Moon and fly them separately in lunar orbit making them the first to experience the eerie feedback. But they weren't the last. Apollo 11 command module pilot Mike Collins also heard the strange sounds, but knew from the previous mission that it wasn't anything alien.