Re speakers: yeah, it is not pleasant. I have had it once in a while (volume increased for some unknown reason, maybe accidental vol + pushing?) but have not yet seen any degradation on XZ2. So, should be OK

Re reboots: no comment, can't tell why

Re presage: English is there and available. French & Dutch - needs someone to make them

Re limited apps: strange, I have noson available. try to logout and login back. if it will not help, file an issue at the official forum

Re Lighthouse: I have 0%, but 27C. Could be Lighthouse bug as it works correctly in collectd/systemdatascope