New large fiddle leaves getting brown spots and yellowing

We got this 5' fiddle delivered a few weeks ago, and it is facing a North East window. The leaves towards the bottom are one by one turning yellow, and some are getting small brown spots or holes, and falling off. We plan to replant it into the larger pot, but didn't want to shock it yet. No new leaves have started forming yet, only losing leaves. What should we do? Should we go ahead and repot it now, and/or switch to distilled water? We typically water it once a week. I thought we might be over-watering, but the soil always seems bone dry even a few inches down. Any help is appreciated!