default views get alpha pager as default

I use default views on one site.
Upon activating views_alpha_pager in the modules page all the default views automatically display an alpha pager (on bottom and top) with blank results, while regular views (made with the ui) remain fine.

Clicking on "All" shows the results, but still shows the alpha pager with _ or # and All as the only paging.
The default sort is by field (sortable table view) and is set to created date by default.
There's no fixed sorting from the sort criteria section.

Also, the default views are displayed both by inserting the views via php and direct path.
The view have use_pager set to TRUE both in the exported php array inside the custom module and in the php function that inserts the view.

Now, despite this problem alpha pager being included by default, i can't find the views api option to force a numeric pager.
In the code taken by exporting the view there's no mention in the exported php array of the type of pager being set to numeric or alpha.
This is the php code pasted into a custom module that owns the default views.

Can the type of pager be specified directly in the php array?

In any case, default views should default to numeric pager when set to TRUE but type is not specified.