Based on the timing (10 minutes) it sounds like the HDMI connection is failing the Copy Protection check (HDCP) that runs in the background during playback every so often. When it fails, an HDMI retry is triggered which will mute video until the Copy Protection is happy again.
This is almost always due to marginal HDMI cabling. Recovery should happen in 1 or 2 handshake tries -- 2 to 4 seconds -- so if you are really experiencing a 10 second drop that would say the signal is even less than marginal. (HDCP is finicky by design. It LIKES to fail.)
Tackle this with the usual procedures for dealing with HDMI cabling issues. For example it could be as simple as just having to pull and reseat the HDMI plugs (every plug from end to end in the signal chain all the way to the Display). HDMI is just friction fit and it only takes a small shift of plug in socket to screw things up -- pretty common with new installations, particularly if you have also switched to new cables that still have kinks in them from the packaging. Insure that each plug is fully inserted straight into the socket with nothing, e.g., cable weight, tugging on it in any direction.
Next, every HDMI cable should be one sold as "High Speed", or "For 1080p", or "Category 2", all of which mean the same thing. Keep in mind that HDMI -- particularly copy protection -- is an end to end protocol, so every active cable in the signal path is suspect. The cable OPPO provides with the player is a good one.
Next, if you have anything else in the signal path, each of those things should be suspect. Bypass them temporarily to see if that cures the problem. This would include daisy-chained cables, adapters, HDMI switches, wall plates (used to dress up the wall ends of in-wall cabling), and any additional gizmos in the signal path such as an external Darbee box.
Next, if you have long cable runs, check to see if that's the problem. Temporarily move the player close enough to the Display to use the normal 6 foot cable and see if the problem goes away. If so, you probably need to upgrade your long cable run.
One thing you can do to test is to lower the bandwidth on the HDMI cable. Turn Deep Color OFF and then try 480p output Resolution. 480p (not 480i) is the simplest HDMI signal. If that works, try 1080i. If that works go back to 1080p. If 1080i works but 1080p does not, then that's typical of marginal HDMI cabling problems.
One other tip: Short cables can also cause problems. Due to technical details of how HDMI works, the sweet spot for cable length between each pair of devices is 6 feet (2 meters). So if you have boxes close together, it is still better to use a 6 foot cable between each pair. Just as some folks use long cables without issue, others will use short cable without issue. It's just that 6 foot length of "high speed" cable maximizes your odds.
Last edited by Bob Pariseau; 05-20-2015 at 08:12 AM.