That "golf ball" sound has been discussed here:Thanks. I think it might be something different though. I can't actually hear anything I can just feel the pedal move a little on my foot.
However, I have had a 'golf ball' kind of noise while going around a corner but it's only happened 2 or 3 times. I'll keep an eye on it though listen for the muffler.
Hopefully it's just the ABS for the pedal thing.
It is most likely the the muffler.