Foaming?

I am getting down on a keg of Wheat Ale, and it served fine the whole time (kegerator with picnic tap, approx. 10' of 3/16" hose. it was about 12 psi. CO2 is in fridge, and picnic hose always stays in fridge. It seemed great all along but now it serves foam, a bunch of tiny bubbles consistantly form in hose when serving. if I pour a couple glasses quick it seems to start to clear to just beer in the line but then bang, another burst of bubbly foam. any thoughts on what this could be? is this normal coming on the bottom of a keg?
Thanks in advance.

what temperature? are you sure the keg isn't partially freezing? are you sure of the pressure? is there a way for you to check the pressure?

Thats a good point I do have the fridge cranked to full cold. I'm not sure on the pressure except just reading the reg gauge. I could try to gear up a 2ndary gauge. Kegs gone now anyway. I'll keep that in mind for my next one thanks. would it freezing a bit cause that?

yup. if it freezes, those areas of freezing are where co2 will start to come out of solution, and will be most evident if part of the dip tube is frozen.