[Alan Anderson]

Putting LEDs in parallel is rarely a good idea. Any slight discrepancy in voltage drop among them will cause the current to go primarily through the one with the lowest voltage, and a shared current limiting resistor will not have the desired effect.

How many LEDs are you using, and what voltages are available to you? Put as many in series as you can, and use multiple sets of series-connected LEDs each with its own resistor.