As a kid the SAME Header was the scariest thing to me, I would have cried so hard if I experienced this when I was little (As an adult I find it a lot more fascinating instead of scary, AFSK is super interesting)
Sounds like a S.A.M.E header crash. The message must not have been transmitted properly, the computer crashed as it was sending out the headers, or they lost power (which would likely lead to the message abruptly cutting off, rather than the S.A.M.E header looping.) However, in any case, they would likely retransmit the message as soon as possible (I don't believe it was a test, because tests are normally run on Wednesday's between 10am-12pm, depending on the office.) But yea, very uncommon to see that.
My WR-120 glitched out on me one time. It did it's regular RWT but after the test, it went off again, but the voice glitched out. I have a video in case my explaining was shit.
for anyone wondering, this is what the SAME headers were "saying": _Edit_ ZCZ_-Easuuu Z_Z_-_Asuuu ZCZC-EAcuuu Z_ZC-EAcucCBb" Edit: decoded it in a different way, the rest is garbage data. And the 5 tones at the end aren't even valid EOM's, if that's what was supposed to be transmitted at the end