I found a fix for the disconnecting sources, I tried this out and it worked for me. Here is a link with some Windows 7 Samba fix.
For those of you that don't want to read - This worked for me
Go to: Control Panel -> Administrative Tools -> Local Security Policy
Select: Local Policies -> Security Options
As shown in Figure 1, there are two settings to change.
"Network security: LAN Manager authentication level" -> Send LM & NTLM responses
"Minimum session security for NTLM SSP" -> uncheck: Require 128-bit encryption
Didn't need to do this -
If problems still exist, one final thing to try is removing the stored credentials for the Samba share. During testing, it's possible that something strange got "stuck" in there. In the Control Panel -> Credential Manager, find and remove the stored credentials for the Samba server.
Hopefully this worked for you as it did for me.