New toy, new problems, tranny noise help!

New to moombas and new to the forum, haven't had much time to search older threads to see if anyone has had similar problems, so take it easy on me. First thing I bought this 06 mobius lsv a few days ago for a great price considering the options and extras, the only hesitation I had was the previous owner just put a new long block in it and it has about 100hr on the new motor, and he wasn't very clear as to why the last one took a dump. But I put it on the water ran the crap out of it and everything worked as it should. So I bought it, well today I took it out for a pleasure Cruz and to listen to the new rev 8's I put on the tower so I took off across the lake and was cuzin a little under 30 and everything was all good and after about 5 minutes at speed I started to hear a popping sound like metal binding then breaking loose and making a pop, so naturally I cut it back down to idle, opened the deck and listened for anything out of the ordinary, heard nothing suspicious. So I paused the music and took off wide open to see if the sound returned, and after a few minutes at speed it the popping noise came back along with a whining noise I put my ear to the floor and it sounded like it was coming from the transmission area. So I throttled down quickly and when I did I got a nice shriek sound that reminded me of a slip/free spin sound. But it still goes in gear forward and reverse and only does it after being at speed for awhile, checked fluid it was a little low but in operating range. This is my first v-drive, don't know much about the setup. Any input would be greatly appreciated!

It's possible the motor was replaced after a failure to winterize and the same event caused other problems that the owner did not know about until the motor was replaced. Sure sounds like transmission or v-drive failure. I would check your flange bolts and all your running gear to make sure it's not something simple.