We bought a house in January and the owners left us the Dolphin 2011 and the DVD to watch. We watched the DVD and put it in the water and to our amazement and luck - it worked wonderfully.
We cleaned it out according to the DVD - went to use it again the other night and it won't sink!
It just stays a float - we have no idea why or what could be causing it. I tried to look online for troubleshooting - but no one has this same problem it seems?