A Revvy is always a good investment. Beats shaking your gun to let the balls fall into the feed.
About your high velocity, just turn it down! I don't know the Infernos that well, but your user manual should have all detailed instructions about tuning your velocity. As far as I know you should turn the velocity down at the back of the gun, using an allen key, but I could be wrong.
You could have a wee stiff spring driving the hammer of your marker, or your CO2 (assuming you're using that) could have heated a bit.
Any looser springs included in your marker's kit? Try that one.