I had my 12/13 app’t jumped up to TODAY (hallelujia!), so I was able to ask my aud-guy some additional questions and try on a size (M) power dome. I was also asking about the feedback management program, and my aud-guy said he wouldn’t run it on me unless I was experiencing feedback when my hand was brought close to my ear. Feedback would indicate some leakage (probably due to poor fit of the dome/mold). He said that feedback management tends to cut out the high end frequencies, so that speech comprehension could be compromised (I’m guessing the sounds like “s”, “f”).
The main purpose of my visit today was to swap out the size (L) Widex power domes with the size (M) Widex power domes. There is a definite improvement in comfort with a slightly smaller dome. Again, I have to stick to Widex or some maker of the dark silicone domes. I may have an allergic reaction to the clear ones.
Sound quality has diminished a bit with the smaller domes, tho. Feh. Speech and noise sound harsher and tinnier again - but not as bad as with the tulip-style domes. I will try swapping in the two sizes to see what I end up with, but quite frankly, I’m happy with the sound of these Opns - especially with the (L) domes.
Ironically (or maybe not, given all the literature out there on these aids) I am down to just a “noisy environment” program (directional). I may even remove that one. For the phone, music and normal listening, Program 1 default gets the job done.
I can’t emphasize FIT enough with these aids! They seem to have the “wow” factor, but if a perfect seal is not achieved with a dome or mold, I don’t think these aids would work for me. I am still in “laboratory phase” trying to find the perfect combination of domes. I may have to wear a (M) in my right ear and a (L) in the left (as my right ear canal is just a sliver narrower).
I also changed the batts in these aids and VOILA! TV streamer worked like an ace. So I think the odd fritzing I had going on the other night was due to the batteries going down. They hadn’t beeped a warning yet, but I was on Day 5 for the size 312s.
Again - SO VERY GRATEFUL to all the knowledgeable folks here, who have not only given me questions to ask my aud-guy, but also answers, that help me get the most out of these Opns. 
You’re ignoring this member’s posts.