I did have a Black IPA a few months ago in Bandon that wasn't quite right but the reason was obvious. It was nearing its best by date because the pub as usual had them hidden on the bottom shelf behind the bar and wasn't promoting beer brewed down the road.
It really just lacked all of the gloriously juicy hop notes that should have been there. I happily drank it as it was still better than anything else they had and I went and had a second one to help clear his stock.
You might have just got an old bottle.
I can't explain the cans though as they are brand new, one batch and they have been fine for me.