Shanling CD -T100 tube CD player problem

My Shanling CD T-100 (mark 1 with the 4 transformers) recently does not recognize that the lid to the transport is open. The problem seems to happen once the player warms up. This condition causes the player not to know when the disc is changed and maintains the track information from the previous CD. Initially I was confused when changing CD's as to why when I skip  to the next track that it would start playing the track in the middle or just not from the beginning of the track. Then I realized that when I open the lid that the player does not indicate "door open". At this point the only way to make it re-read a new CD is to power cycle it and then it will read the new disc. As I stated the problem does not happen until the unit warms up. When I first turn it on it works fine. From what I can see there is a sensor in the rear of the transport that detects when the lid is open and not a micro switch. I would say that the sensor is bad but it almost seems like it could be the micro processors since the sensor works fine when first turned on for the day. Not sure how available parts are for this thing even though Shanling is still in business I cant get them to return my emails and I am trying to avoid calling freaking China to talk with someone. However if I had an idea of what part I need I would call them and order the part. Just curious if anyone else with this component has had the same problem and what was done to resolve it. Next step is to take it to a tech I guess and have them troubleshoot it.