Amazon prime will not chromecast and they probably have some encoding or other way to make it hard to replicate sound and video other than streaming through browser.  I would check with amazon primes support about why.

Is it also happening with YouTube?
Have you tried maybe sites like Grooveshark or Bandcamp? (For testing purposes of course):
Please let me know.

I'm thinking it's a hardware issue possibly...just last night it did the same thing only I wasn't even on the internet. I had finished listening to a folder of music...the computer sat idle a bit...when I opened another folder to listen to more music it had lost connection. I could here the speakers pumping out intervals of sound but the solid connection was gone.

I see. Where did you buy these speakers from?

Well the speakers I have now are the Logitech via Amazon (along with a Bluetooth adapter) but these same symptoms happened with the Creative Lab speakers I had purchased originally for the laptop...I wound up returning them thinking they were defective, now I see that the problem lies elsewhere...what do you suggest?

Have you tried updating the Bluetooth Driver, or even the Audio Driver?

According to the device manager the drivers are up to date on both...do you have any suggestions on drivers to download?

I can only suggest using the ones from our website for the Audio.
If it is Third Party Hardware/Software. I'm afraid my knowledge is quite limited. 
My apologies.