ComboBox not filling with code - vb.net

Question

I have the following code:
Using conn = New SqlConnection(connStr)
Dim sql = "SELECT [CATEGORIA], [AREA] FROM [CATEGORIAS] WHERE ([AREA] = #AREA)"
Dim sqlCmd = New SqlCommand(sql, conn)
sqlCmd.Parameters.AddWithValue("#AREA", CStr(PublicLogin.Area))
conn.Open()
Dim ds As New DataSet
Dim da As New SqlDataAdapter(sql, conn)
da.Fill(ds, "CATEGORIAS")
With cboCat
.DataSource = ds.Tables("CATEGORIAS")
.DisplayMember = "CATEGORIAS_AREA"
.ValueMember = "CATEGORIAS_AREA"
.SelectedIndex = 0
End With
End Using
It should in theory fill the combo box right? It doesn't. It doesn't give me any errors or anything; the combo box just sits there empty. I am pretty sure the query is working well and its grabbing the correct info but the Combobox doesn't fill. If I take the where query out it fills the CB with 'System.Data.Row...'
UPDATE: Working code in case someone needs it;
Using conn = New SqlConnection(connStr)
Dim sql = "SELECT [CATEGORIA], [AREA] FROM [CATEGORIAS] WHERE ([AREA] = #AREA)"
Dim sqlCmd = New SqlCommand(sql, conn)
sqlCmd.Parameters.AddWithValue("#AREA", CStr(PublicLogin.Area))
conn.Open()
Dim ds As New DataSet
Dim da As New SqlDataAdapter(sqlCmd)
da.Fill(ds, "CATEGORIAS")
With cboCat
.DataSource = ds.Tables("CATEGORIAS")
.DisplayMember = "CATEGORIA"
.ValueMember = "CATEGORIA"
.SelectedIndex = 0
End With
End Using

Answer 1

Its empty because probably the query returns nothing. Notice that you are not adding the parameter to the final query on the sql variable.
You create a command with the query and the parameter but you never use it, so when you select all the values WHERE ([AREA] = #AREA) it returns nothing.
Try this:
Dim da As New SqlDataAdapter(sqlCmd)

Answer 2

This looks odd to me:
.DisplayMember = "CATEGORIAS_AREA"
.ValueMember = "CATEGORIAS_AREA"
It should probably be something like this:
.DisplayMember = "CATEGORIA"
.ValueMember = "AREA"
From MSDN on DisplayMember:
Gets or sets a string that specifies the property or column from which to retrieve strings for display in the combo boxes.
EDIT: You also need to replace this:
Dim da As New SqlDataAdapter(sql, conn)
with this:
Dim da As New SqlDataAdapter(sqlCmd)
Otherwise your parameters are never used.