Changing U-verse channels causes momentary picture freeze.

Changing U-verse channels causes momentary picture freeze.  This problem used to be random, sometimes going away completely for a while.  Now the freeze has become a standard operational feature.

I've tried "cold-booting" the ONT, BGW210-700 and the VIP-2250 STB.  Even went through the AT&T U-verse online troubleshooter. 

No joy!

Is this now the new normal?

Any suggestions?