LTC3780: What is best practice to filter voltage spikes at the output?

Hi there,

I have designed a circutiry using the LTC3780 (BuckBoost converter). Everything quite close to each other, certain things may be designed better.

Now, the output experienc huge voltage spikes, at about 200 mV - 500 mV, depending on the input voltage (4 V - 24 V) and the output load (i.e. 100 mA - 2 A), see pictures below. However the spikes are huge in any case. Roughly said, at the output I have 330uF Elco and 100 nF and 1uF keramik capacitors. At the input a 22 uF Elco. 

Everything seems to be as close as possible to each other (i.e. also a area for the switching node around the coil (4.7 uH, 9.4A, Coilcraft SER1360-472KLB). ROHM QH8KA4TCR as Dual MOFSETS N-Ch.

Having these spikes, what would you recommend to get rid of these spikes? 

When measuring the spikes I placed the probes very close to the input and output and minimized ground loop (max. 2 cm).

Thanks for any input.