HMC504LC4B power supply issues, HMC981

Hi.

I'm senior engineer at Indra system. I'm debugging a board of our own and I'm having trouble with HMC504LC4B part, specifically with the power supply. I'm using an HMC981 active bias controller for the HMC504. When I enable the supply the drain and gate voltages a very unstable. In the following picture you can see the drain voltage.

Can it be a problem of instability?. The next think I'm going to try is to change the gate decoupling capacitors. Currently I've got three capacitors of 100 pF, 10 nF and 4.7 uF. However in the datasheet of the HMC981 is stated that a 10 uF capacitor should be place between the gate and the ground in order to guarantee stability.

I'm using the footprint shown below. Is it a problem?. There was a missanderstood when designing the board and we did not use the footprint of the evaluation board of the amplifier.

Best regards,

Ruben