MH bulb ringing?

Ya this is what I thought at first. But after thinking about it I had been running an Astralux bulb in there for a year with no buzzing or any other problems. The seller of this set up also offered Ushio 10k bulbs as a choice when ordering the retrofit. After rereading the thread recently, many people picked the Ushio bulb and had no complaints about buzzing or any other problems with the kit.

This is the most obvious cause of the problem, but after reading the bulb it required a 4 mV pulse start ballast, which this one is. They also dont make 70 watt DE bulbs in any of those ansi codes im pretty sure. You may be right and the astralux bulb was a different ansi code, but due to it not being made anymore I cannot find the code for this particular bulb. I also did not receive the box for the bulb when I ordered so I have no way of knowing.

Thanks

Bill