Digital Ovulation Question

Question for you ladies! I have been using Clearblue Easy Tracker to track my Ovulation. This is the test where it is a blinkey smiley face for high fertility and a non blinking smiley face for peak fertility. I usually ovulate CD17ish according to the cheap little sticks. This month I started using the digital tests and have gotten a blinking smiley face for 4 days in a row. No plain old smiley face. Has this happened to anyone else? I have had all the signs, including cwcm, that ovulation has occurred and my cheap sticks were very positive yesterday and day before. Any advice from you ladies?