I notices that when milling a board who’s NC code was generated by Copper CAM, there is an offset between the drilled holes and the etching of the tracks.
Once I drill the holes, I’ll enter an offset of X-1 and then zero Mach3. That shifts the subsequent steps (etching, cutout) by 1mm to the left.
On closer examination, 1mm may be too much. I will try 0.8mm on the next board to see how it turns out.

UPDATE:

It turns out that my mill is not perfectly perpendicular to the board. The error comes out of the fact that the end of the tool for the engraver mill and the drill is much different and when a small rotation is added to the mill head a linear difference is observed.
I adjusted the head rotation and now both the milled and drill points line up perfectly.

Looking into how I’m going to get audio into the different rooms of this house where there is no structured wiring in behind the walls to take advantage of.

http://www.avsforum.com/t/1341706/any-alternate-product-just-like-sonos

http://www.musicmultiroom.com/

UPDATE: pricing out some components, and I think I will go the DIY route with a squeezebox backbone. I have a squeezebox classic and radio already. In each room that I just want some music that doesn’t need to be played at loud volumes I can put a squeezebox radio (they go for about CND$100). In the living room I can use a squeezebox classic or squeezebox receiver with some quality speakers and a small class T amp to drive them. As a reference, the Sonos Play:5 is $450. For that kind of money I can put together much better components (speakers, amp) that will be much louder.

For compact class t amps, read this: http://madgoat.hubpages.com/hub/High-quality-inexpensive-mini-power-amplifiers

More on what small amp to use with a squeezebox: http://forums.slimdevices.com/showthread.php?91027-Stylish-tiny-amp-for-Touch/page1

100W Class T amp on ebay (w/ power supply): http://www.ebay.ca/itm/2-X-100W-Class-D-Audio-Amplifier-Combo-Kit-w-24V-350W-Power-Supply-TK2050-/350604100288?pt=US_Home_Audio_Amplifiers_Preamps&hash=item51a1a202c0#ht_4095wt_1080

A lot of the class D or class T amps seems to be based on the Tripath integrate amp chips. TA2020 is a 30W amp(@ 4 Ω), TK2050 is a 100W amp (@ 4 Ω) .

This also looks like an interesting option. In wall keypad to control with amp built in: http://www.pyleaudio.com/sku/PVC8U/In-Wall-Background-Music-Amplifier-with-USB-And-SD-Card-Player-With-35mm-Input-Jack-For-iPodiPohne-and-Volume-Control