When I create workouts in Garmin Training Center and download to my Foreruner 305 I get mixed results when they beep. I created a workout to run 29 minutes, walk 1, then alternate running 9 minutes with walking 1 for the next several miles. I thought it would be at every interval but it only beeped after the 29 minutes is up. Anyone know where to control this? I can't figure it out. :(