What part are you using? I want to see the data sheet.
Some times I add a 1 to 10 ohm resistor to the output of the amp to separate it from a capacitor load.
Amplifiers don't usually have the capabilty to take on large capacitive loads. So, you'd need an outside source compensating for the capacitance. Does that make sense?
And if you don't have a ton of capacitance, there could be a different issue at play.