Special for AZbox Ultra and Premium+ there is a new kernel ( 3.4.4 , note : not for the older images based on the older kernels! ) for faster zapping.
Some users have noted that zapping speed is slow on Premium+ and Ultra.
We have found problem in compiler as part of OE, until we fix it we recommend people which want faster zapping on Ultra and Premium+ to install this kernel with AZUp 2.2.6
Start AZUp 2.2.6, enter IP address of Ultra or Premium+, select Only kernel field (see picture) and press GO.
This kernel can be used with AZBox Elite and Premium as well.