Hi, I have not used Philips bulbs but I suggest contacting Varilight through their website, they are very good at helping.
I had the same issues, and they sent me a later revision of the dimmer module that had newer firmware, and it resolved the issues.
When you contact them, send the codes that are written down the side of the dimmer module on the back on the plate, as they will ask for this.
Depending where you bought it, it may be an older dimmer, and with LED technology moving so fast, its simply not capable of driving your bulbs properly