Both of you should definitely write up the details of your cabling and settings, along with the bar-code numbers from the packaging of the discs you are using to replicate this problem, and email that to OPPO Tech Support.
Be sure to mention that it is happening with DVD-Audio discs as well.
I've not seen any indication of this being a wide-spread problem, so it may be peculiar to the particular discs you happen to be using, or to the specifics of your settings in the 105. For example whether or not Quick Start is in use. It may also be a case where the key factor is what you were playing in the 105 just prior to the problem surfacing each time. For example Pandora app, or a normal CD disc. Try to keep track of what you were last doing with the player prior to the problem and see if you can spot a pattern.
For me this occurs with all discs.Ihave tried at least 20 and get the same results. Happens when Ifirst power my system up and after watching a bluray movie. Alway first get only 2 channels. Must then recycle the player and then plays correctly. Evrytime. At least its consistant.