Several suggestions:
Disable Multi-channel and see if it makes a difference. I'm not sure it will work with your network configuration.
Your network configuration may be an issue. You have two bonds (bond1, and bond2) each with a single NIC, but you've set the backup mode (1). Backup mode won't work with a single NIC.
Since you are using AD, I suggest you install this plugin and switch to the 'tdb' database. The 'hash' database is deprecated and has been known to have issues. Caution: You will have to redo all your permissions when you reset the database.
I also notice all your shares are set public. Even though you have many set as hidden, it's not really a good idea to share everything as public for security reasons. Why use AD with no permissions being set on any shares?