Yes, I also tried plugging it directly into an Arduino and could only power one color at a time, unless I dropped the current for all channels to 1/3rd. This makes sense since each channel draws 20mA which is near the maximum for the I/O ports. You might be able to get more out of the ShiftBrite by using the jumper on the bottom that bypasses the internal regulator, but probably run the risk of damaging the Arduino.
I'm not exactly certain what's going on with your second issue. This is when the device has been running for more than an hour? I doubt it's a data corruption issue; that's a known effect where any noise on the data lines can set configuration registers to invalid values. The solution is to periodically write the configuration registers. However, your problem seems to be time-related. I would suspect heating of the chip. When you touch the ShiftBrite controller, is it very hot? The chip will keep turning itself off if it gets too warm. This can happen if the power supply voltage is high; any excess voltage needs to be dumped as heat by the chip regulator before it goes to the LED channels. I am using 5.5V supplies mainly, what is yours?
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Yes, I also tried plugging
Yes, I also tried plugging it directly into an Arduino and could only power one color at a time, unless I dropped the current for all channels to 1/3rd. This makes sense since each channel draws 20mA which is near the maximum for the I/O ports. You might be able to get more out of the ShiftBrite by using the jumper on the bottom that bypasses the internal regulator, but probably run the risk of damaging the Arduino.
I'm not exactly certain what's going on with your second issue. This is when the device has been running for more than an hour? I doubt it's a data corruption issue; that's a known effect where any noise on the data lines can set configuration registers to invalid values. The solution is to periodically write the configuration registers. However, your problem seems to be time-related. I would suspect heating of the chip. When you touch the ShiftBrite controller, is it very hot? The chip will keep turning itself off if it gets too warm. This can happen if the power supply voltage is high; any excess voltage needs to be dumped as heat by the chip regulator before it goes to the LED channels. I am using 5.5V supplies mainly, what is yours?