Chrome Dev v50 (the version that will, after testing, feedback, and fixes, become Chrome 50) has, with a little flip of a chrome://flags switch, solved the problem of Chrome-Android's issues with currentTime and duration on constant bit rate files (a problem that's been around since v40, and has since 'infected' Amazon's Fire platform where the webview is based on Chromium v41). Yay. Hopefully it is a general purpose solution in Chromium and not specific only to Chrome, so the other Android platform browsers can inherit it in due time. For FireOS, that may take 6 months to a year of the workaround, but at least the workaround isn't useless.
Testing with it today finds that it performs just as well as Chrome Desktop and Firefox Android.
(The fix? They're 'unifying' the media libraries to the Desktop version, rather than relying on the underlying OS and its inconsistencies. go fig.)
I may still do some testing with Howler to see if the Web Audio API does better than the <audio> tag at working around it.
Speaking of FireOS, I am aware that the screensaver on FireTV/Stick sometimes 'crashes', causing the app to close and making it return to the home page. I will try to debug it, but I'm so far liking the color-patterns on the regular playing page that I may just rely on that from now on. If you really like the screensaver mode, let me know, 'cause I'm not 100% convinced it is worth the trouble right now over just working on more improvements to the main playing page that all platforms need.
Currently, work is on hold on SubFire while I work on the upcoming SubFireRadio page, which will allow you to define rules for 'smart' shuffle playlists, and regenerate the playlist's file list directly on the page, and also save it as a 'station' to generate in SubFire on demand. I hope to have that finished by the end of March, with a 'beta' release likely in a week or so.