Layer fade-out animation works for video but not for image or text box

Hello,

I am attempting to set up layers with single objects (one layer is a video, one is a text box, and one is an image) that fade in and fade out at given times. 

The video layer works fine: it fades in at the beginning of the timeline (using a trigger) and fades out when it reaches its display end point on the timeline (so no need to trigger its fade-out).

My text-box and image layers faded in at a set time on the timeline (using triggers connected to the timeline) but either did not fade out at the designated time or did not fade out -- they simply vanished abruptly.  When the layers did not fade out at the designated time, I noted that they remained visible for 35 seconds before fading out.  Always 35 seconds.  

I found that if I attempted to trigger the layers' fade-out, that overrode the animation, resulting in the layers abruptly vanishing.   But without a triggered end-time, the layers would go on for 35 seconds and then fade out.

I tried different ways of telling Storyline to fade out the layers: a timeline trigger created within/connected to the base layer, a timeline trigger created within/connected to the layer, adjusting the display time of the layer object on the timeline, and coordinating the fade-out of the layer via trigger with a dummy object on the timeline (which is placed to the side of the canvas so not visible).

To get around this for the time being, I moved my text box to the base layer and used States to have it fade in and out accordingly.  It works fine.  I will do the same with the image layer.

If anyone has a solution I would appreciate it.  Am I using layers incorrectly?