Silences based on calendar entries? Do you mean at specific times and dates or do you mean that the things you put into your calendar cause changes to your sound profile? If you mean the former Tasker may be able to help. You can go on line and get a free 30 day trial of Tasker. If you go to the Play Store I don't think it will offer you the trial, at least it didn't. Then go to taskerwiki and browse the profiles there to set one up for the things you want to do. Tasker does a lot more than control your sound but right off the top of my head it would work for the a fore mentioned need. However for the latter mentioned I'm not sure I know of anything that would offer that. Something you might also do is go to the page for the app you have at the Play Store and scroll to the bottom and see what Google is saying would be similar app to the one you have and liked, and you can see what other people who've looked at it have installed. While you are there you might also use the contact dev. link and report your issues to the app dev. and see if they may already be working on a fix/patch/update. Most dev.s, in my experience, don't pay attention to reviewers comments or act on them very quickly even when there's been a huge outcry, so I always recommend that you contact them directly. If it's a good app it probably has a good dev. willing to respond to customers.
GL
P.S. On a side note there have a few threads about sound issues with the One after the update to 4.4. You may want to look at some of those threads just to see if your issue is similar in any way to those. It may turn out that it's not the app. I know one was something like 'sound issues after 4.4' and another was 'Tasker sound issues/problems' and there may be others if you do a search.
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