Class b amplifier - feedback problem

Try removing CB / C8, whatever it's called. 330pf @ 22kHz = 22K, so effectively you have 10K feedback at 22kHz, which increases. Probably sounds bassy right? Or would do if C9 was bigger. There you want all frequencies passed, so need a bigger cap. Go for about 4700uF.

I haven't seen a capacitor in a power amp's feedback circuit before though. Only in tone controls and filters...(baxandall etc)

Hope that helps :)
 
C14, near the input, should be removed. It may make the TL082 unstable, and cause oscillation.

I agree with GabbleDuck that C8 should be removed, and C9 increased to a few thousand uF.

C3 could be removed as well. It also rolls off HF above about 23KHz, but maybe that's wanted?

It's not going to be a great amplifier anyway - only about 2W output power, and it's mono, not stereo.