Received a Pace XG1-V3 -- That Solved the Audio Problem

No. In fact, the V1's are ancient and very, very slow.

The box I was sent is a xg1-v3.  Is there a picture quality difference between that and the xg1-v4 other than not doing 4K?

Thanks

no. the xg1v3 is only known for loud cooling fan bearings.

Thanks you for the comment, Rustyben. 

Switching to this v3 box, from the xg1-v4 I'd been using was a case of "if you can't raise the bridge, lower the river."  I have a Sony 75Z9D that the v4 worked fine with since 2017 when I got both the TV and v4.  About six months ago, Comcast updated the box's software (from 131.1.2 TO 132.1.1) and two things happened, both bad. 

First, every time I'd change the cable box channel, the audio would drop (either to the TV speakers or the connected soundbar) for 8 seconds, then reconnect.  It would do this on every channel change if the box was in the Auto Detect mode.  If you changed the box to "stereo" the audio drop would not happen.  The other problem was that the box (while in Auto Detect) would not switch based on audio signal.  The result was, programs and commercials in stereo didn't trip the box out of 5.1, so stereo material would have phase-cancellation, and be barely audible.  I can confirm the box's software update was the problem because I got a "factory fresh" xg1-v4 from the xfininty store and it worked fine, until a few nights later, when the 132.1.1 software that came on the new box, was updated.

So now I've just connected the xg1-v3 (with software version 134.0.0) and there is no problem with both audio issues.  I don't know whether a future update with make these two problems reappear.  

About four weeks ago, I got through to a Senior Tech Rep in Philadelphia.  I'd spoken with him four years ago when he was working for Neil Roberts.  (I'm told Neil had moved over to work with Dolby Inc and is now down here in Florida.)  This rep told me there is a known problem with some Sony XBR televisions and the newest v4 boxes.  It's something they're working with Sony on, but I guess the process is a slow one.

So, as of last night, the new v3 box is connected to one of Sony's finest televisions, and the picture on cable channels looks fine.  The size of the v3 (big and heavy) is not a problem, since it's tucked away in a (ventilated) cabinet, and for the moment I'm able to hear the correct audio and not have to wait for the audio to reconnect after any channel change.

With all that's been going on for the last 18 months, it was a low priority issue, that now seems quelled.

The audio problem is probably not the X1 software, but the box firmware, which is lower on that About screen. With the Xg1v4, it's currently on 4.8p18. I think it's when 4.8p9 first came out back in May 11 when the DD+ audio issues started (IP-based audio that is 2.0 is passed on as 5.1, preventing my receiver from doing surround processing.) My notes show that was software version 130.0.0 at the time. 131.1.2 came out around June 8. Before all this, it was on firmware 4.6.

Should also add that the dates shown on that About screen are when the software/firmware is built, but it's not released to boxes until a few days or weeks later.

Thank you, that is enlightening.  Do you think an update to my v3 would bring the problems back?

The firmware is specific to each box. The basic version number may be the same, but the first part will be different. For the XG1v4, it's AX014AN. Each is specific to certain hardware. There was probably some update to something specific to the v4 that is causing the audio issues.

"The firmware is specific to each box."

Before I converted to the v3, I moved around the three v4's I had in the house.  One was on this troubled 75Z9D, one was on a Sony 900F (which uses many of the same components as the Z)  and all boxes had the same issue when conncected to the Z9D television.

The 900F, with a v4 never had either audio anomoly that the Z9D had.

andyross, thanks for your clarifications.