Iteration in safari over 2000 rows slow, id column value 5-undefined

[SunSha]

I have a table with 2000 rows, automatic id with auto increment. Indexed on id and 3 other columns. (3 columns makes a composite key).

When I open the object store index (on id or any other indexed column) , it takes more than 2-3 minutes to iterate. This only happens in Safari (Desktop and iOS). Chrome, Firefox works fine.

Also If I check DB in firebug viewer, the id columns shows this value for all the rows: '5-undefined'.
Not sure if this is an issue or mistake of mine.