private void EditOffset(int selected)
        {
            // Will need to pass in the currently selected item
            frmOffset dialog = new frmOffset(frmOffset.Mode.Edit);

            dialog.SetAmp(offsets[selected].Amplitude);
            dialog.SetPhase(offsets[selected].Phase);
            DialogResult r = dialog.ShowDialog();

            if (r == DialogResult.OK)
            {
                var newPhase = dialog.GetPhase();
                var newAmp   = dialog.GetAmp();
                offsets[selected].Phase     = newPhase;
                offsets[selected].Amplitude = newAmp;


                lsvOffsets.Items[selected] = CreateListViewItem(offsets[selected]); //grabs selected items from offsets list, stores in listviewitem, adds to listview
            }
        }