Calibrating a BOSS TU-2 Tuner?

Forgive me if this has been covered before...

I picked up a Boss TU-2 Tuner in a pawn shop for about $25.00, pretty good deal I thought until I tried to use it on a gig. It tunes flat. I know about the Flat & Double Flat settings; that is not the deal. In Chromatic, Guitar & Bass modes, stream or cent, the tuner tunes flat (I A/B'd it with my old TU-2 and a newer Polytune Iphone app). Is there a way to re calibrate a TU-2 to A440? If not, then I have a $25.00 paperweight...I guess next time I buy a tuner I'll bring a tuner to check the tuning of the tuner...;-)

Hmm haven't heard about a digital tuner needing calibration. Maybe the iphone app is sharp?

ive noticed a difference between my korg handheld tuner and my tu-3 aswell, havent found much out about it either.

Google the manual

you probably already got your answer froma manual or somethin', but...

Yes, you can re-calibrate it by clicking to a mode and setting "A" anywhere you want from 428 (I think is the low) to 440-somethin' as the high. You won't mess anything up by snooping around on the what, three buttons, so go for it.

Happy Tuning! Hope you work it out : )

That's surprising. I plugged a function generator into my TU-2 for fun one time, and it was dead on 440 Hz.