Check you have a suitable voltage for phantom power (they're quite thirsty), check that voltage under load for the mic. Check the wiring in the cable. They will pick up and return voltage down the earth if pin 3 isn't very good or is indeed off altogether.
Of course, check the settings on the mic that they're not set to a lower pad setting and that the pattern is suitable for what you are recording.
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Check you have a suitable voltage for phantom power (they're quite thirsty), check that voltage under load for the mic. Check the wiring in the cable. They will pick up and return voltage down the earth if pin 3 isn't very good or is indeed off altogether.
Of course, check the settings on the mic that they're not set to a lower pad setting and that the pattern is suitable for what you are recording.