I purchased a Harry Potter LionChief Hogwarts Express Ready-to-Run O-Gauge Train Set (6-83620) on Nov 11, 2016, as a Christmas gift.  After Christmas my family played with the train, first running it around the Christmas tree on a small 4'x4' board.   A day or so later, we moved the train to our 12'x8' train table layout in our "train room."  Altogether the train probably ran for two to three hours, although my wife said it was more like 45 minutes, before we began experiencing problems.  First, the tender speaker began to make crackling sounds without us pressing any of the sound buttons on the remote control.  A short time later, the train stopped responding to the remote control altogether.  Naturally I changed out the new batteries with other new, right out of the package, batteries.  No help.  I contacted Lionel and they quickly arranged for me to return the train to them and they furnished me a new engine, tender & remote control.  Today was my first opportunity to run the new train.  Frustratingly, the train ran for about 10 minutes before the new tender began to make crackling sounds from its speaker without me pressing any of the sound buttons on the remote control.  After another minute or so the train stopped completely and would not respond to any remote control commands - no chuffing, no bell, no whistle, no announcements and no movement, forward or reverse.  Then I tried something I don't think I tried with the first train - I removed the tender from the track and only left the engine on the track.  Wala - it ran.  Of course there are no sounds, but it runs.  As a side note, my two other LionChief trains are running fine.  Anyone else having problems with LionChief Hogwarts Express O-Gauge Train Set (6-83620) ?   
Thanks.
Jim Brennan