Galaxy S8+ occasionally gives off a brief 3 tone signal. Why?

After two years of use my Samsung Galaxy S8+ split open. Samsung original repair shop told me the battery had swollen and changed it one week ago.

The phone works, but it now gives of a signal (~3-4 falling tones?, quickly). The signal comes irregularly, maybe once every 1-2 hours at home, charging. It often comes after I pick it up and work a little. I have held the phone still when the signal has sounded.

I have only heard the signal once when not charging.

The reason I take this seriously is that I once had an old Galaxy Note 3 that started giving off the same signal frequently. After a while it did not charge well. I had to turn this phone off to charge it. It was thoroughly investigated at Samsung repair shops but no error found. Battery, charger, cable and finally internal charging components changed (not at original workshop). But its charging never recovered. (This entire paragraph was about my old phone.)

I run optimization and only few apps at the same time.

When they changed battery last week they demanded that I removed the lockscreen and they connected the phone shortly.

I asked today at the workshop and they cleaned the contact. I have not used the phone much after, but the signal has come once more, when not charging.

So far it charges OK, but a new battery has not improved usage time.

What is the reason for the signal? Will this phone too develop charging problems? Can I do anything about it?

The last question is a little conspiratory: Does Samsung introduce software on older phones to make them less functional by not charging well?

Edit:

I can now say the situation is not immediately connected to the charging. Today the signal has come three times when using the phone without it being connected to the charger.

How to prevent brief audio cut-outs when using sleep aid apps

When attempting to use an app like Relaxio or Sleepo to drown out background noises when sleeping, I am frequently awoken by the sound cutting out for a fraction of a second. This occurs roughly every 30-90 minutes on average and largely defeats the purpose of using the app in this manner.

Reviews of the apps in question indicate that such problems are very rare, yet I am experiencing this issue on both a Samsung Galaxy S4 and a Samsung Galaxy S7.

What measures can I take (not excluding rooting the phone) to make these apps work properly?

Ubuntu 19.04 brief feezing randomly for 3 seconds

I am using a Laptop Dell Inspiron i15-7567 with Intel Core i7-7700HQ processor, Nvidia GeForce 1050 Ti and Intel HD Graphics 630; using Nvidia driver nvidia-driver-418 (proprietary, tested).

I upgraded from 18.10 to 19.04 and everything was really faster than before.

Recently, the system started freezing for approximately 3 seconds randomly (returning to normal after the 3 seconds). Sometimes I am just moving the mouse. And sometimes it happens when I am starting an application. It can take hours or minutes to happen.

I have think this appeared after upgrading to the new 5 kernel or after installing Slimbook Battery. I have 2 applets installed: Dropbox and SlimbookBattery.

I already contacted Slimbook and we could not find anything that could be causing it. I tried to uninstall the slimbookbattery and the nvidia driver, than install nvidia… without slimbookbattery, and it still froze.

The short freezes seem to happen only when logging in using nvidia (I am not 100% sure yet). When SlimbookBattery is On and when it is off.

Could the SlimbookBattery have changed anything in my system that is not coming back to normal even when uninstalling SlimbookBattery?

Could the new linux kernel not be 100% compatible with my laptop?

What can I do to try to find out what is happening? Any important log to investigate?

I am trying to figure out the cause before trying to reinstall Ubuntu.

A brief history of Bitcoin (BCH) and the opportunities it presents for your business

In August 2017 the bitcoin blockchain at height 478558 forked into 2 different paths. One blockchain would now start accepting bigger blocks to bring back Bitcoin's original features of peer to peer cash with low tx fees. This was BCH. The other blockchain, would keep blocks small and introduce segwit which separated signatures from blocks to slightly increase the block size limit. This blockchain is known as BTC. BTC and BCH have the same identical blocks till height 478558, afterwards…

A brief history of Bitcoin (BCH) and the opportunities it presents for your business