Pixim212DIR, SENS212DIR and SENS212VIR have same power design. They seem a little sensitive to ground noise comming through AC24V power box which is not grounded well. We are redesignning power circuit of them and will release them soon.

**When does it tend to have distinct ground noise?**
Since PB9AC/2.5A, PB16AC/5A and LPB9AC/5A have only hot & neutral but NO ground prong , they tend to have ground shift . And, it could end up showing wavy noisy if camera power does not fully isolate the noise comming from power line. Those three AC power box will come with ground prong in the end of March 2010.

**How can you avoid that noise for the meantime?**
1. Use Individual plug-in power supply. (This gurantees the best result out of all other solution. Both AC & DC works good.)
2. Use DC Power Box with good gound such as PB9DC/5A, PB18DC/10A, LPB8DC/13A, LPB16DC/25A
3. Use AC power box with good ground such as LPB18AC/10A.
4. Ground Isolator does not help much in this case.