Harrison:
Do yourself a favour. Go to Radio Shack right now. Get the cheapest analog Volt Ohm meter they have. It's less than $15. Run your rig until you experience a problem... Then, measure the voltage across PINS 1 and 2 on the XLR outputs of the M148. PIN 1 negative, PIN 2 positive. If the voltage is close to 48, like 47- 52v, the m148 is not the problem. Hell, I have a VOM I can give you. I think you should have one.
Chuck