Thanks for the reply. I can well believe I may have a counterfeit. I bought my supposed R3 arduino as part of an Arduino starter kit on Ebay. After the package arrived I was sent a message by the seller saying they had been delisted by Ebay on account of being an unauthorised reseller....needless to say I haven't replied or had any further contact with them. My board has performed as expected in other circuits that do not use the I2C bus. Here are the photos as requested.
