Driving LM3886 at 100 KHZ in Bridge Tied Load (BTL) configuration?
Your load looks  mostly resistive, not capacitive. I think most design include a large capacitor between the speaker and the driver to block DC since you're only interested in audio. Then it'd be a capacitive load (maybe that's the intent?). Anyway make sure you don't use a polarized capacitor.

Your AC coupled input is too heavily filtered. You need to reduce that 22kohm. 

You don't need that large filter on the mute pin either unless you're actually using it.

You might want to add a capacitor in parallel with your feedback resistor to provide the high frequency filtering.

Did you read the datasheet? It's got some good design tips.