It seems that you are having some issues when using the SlingLinks on your local area network (LAN).
We would like to know if by any chance you are using any kind of network device besides the SlingLinks (such as network extenders). If this is your case, I recommend you to remove them and test the connection using only the SlingLinks, since they may cause an unexpected electrical interference.
This could be the main reason for this unexpected behavior. Make sure to follow this recommendation and let us know how the SlingLinks work for you.