VB6 accessing MDB (microsoft access) database slow but only after insert/update

I have a vb6 app that uses MDB as database. This MDB only has tables and data. The VB6 app has all the user interface and executes sql queries, edits, updates, etc. I open the VB6 app on two different computers on network at the same time. The mdb is in one of the pc's which I call the "server". It's a common share UNC path. I open the VB6 app in both machines. In the first, it opens the mdb locally. On the other, through UNC path. It works fine, till I, on the first pc, the "server", insert/add a record in any table. Then, all queries on the second pc, the "client", get very slow. If I close the app on the client and reopen, speed is normal again. But if on the server I add another record in any table, queries get slow on the client again. Any help thanks.