When Coby learned to bark, we used pennies in a can. Worked perfectly. But after a while, that lost its effectiveness. We moved to a spray water bottle. That worked great. After a while, it lost its effectiveness. We now use one of the electronic sound devices that is push button (not automatic). It has been working great. We have been consistent with each method and each method has worked for months before losing its "appeal". So my suggestion is to try one at a time with consistentency and see what works.
I love my baby, but to me personally, a Yorkie's bark is not exactly music to my ears.
