Sansa e260v1 not reporting correct battery drain?

[rubyiris]

When the screen is on, the battery drains 1% every few seconds, and occasionally goes back up. After the screen times out, the battery eventually goes back up to where it's SUPPOSED to be.

Also, the battery is far less on rockbox then it is on the default firmware. I don't play around with the player much, if at all, so that's not an issue.

Also not sure if this is relevant, but my hold switch is broken and I'm forced to keep it permanently unlocked, and keep the player somewhere where I won't accidentally press buttons.

Most of my library is 160~192kbps @44.1mhz MP3 with some 320, and some 128 and lower.

The player IS about 5 or so years old, but the battery is still going strong under the default firmware, but ultimately I'd PREFER to use rockbox. a final bit of food for thought: Whichever the most current firmware was in mid-2009 was, the battery was awesome, lasting more than the original 20 hours, but when I upgraded to the most current firmware last month is when I've been getting the firmware problems. Any chance the current firmware is just buggy?

Let me know, thanks!

[saratoga]

Also, the battery is far less on rockbox then it is on the default firmware. I don't play around with the player much, if at all, so that's not an issue.

Did you test or are you just assuming?  Battery should be much better in rockbox.

Anyway it sounds like you have something wrong with either the battery or the ADC that reads its voltage if you're getting random drift in the battery readings.

[rubyiris]

Tested. Shuffling my library with moderate skipping, I get about 8~10 hours of use before the thing powers off.

Played with the original firmware yesterday/today, got to about 19 hours before it shut off. (About the time I posted the topic.)

Before I upgraded, I could usually go about two or so days of near-constant use before it would power off.

I don't think it would be the battery itself if I get near-factory spec battery life with the old 2009 rockbox firmware, and the original sansa firmware. I won't rule out other problems, though. That's why I came here. :3

[saratoga]

When it powers off, does the OF agree that the battery is dead?

[torne]

When the screen is on, the battery drains 1% every few seconds, and occasionally goes back up. After the screen times out, the battery eventually goes back up to where it's SUPPOSED to be.

This part sounds pretty much exactly like how a battery that's just old would behave: under a higher load (screen on) its output voltage sags due to increased internal resistance. We rely on the output voltage to estimate the remaining capacity.

This potentially could also explain an early poweroff compared to the OF: if Rockbox thinks the output voltage has gone too low to safely continue using the device it would shut down. Possibly the OF has different thresholds?

Of course, the latest version might actually be using more power than the old version for some reason *as well*, which would make the sagging voltage under load more severe; but a battery that's 5 years old *is* going to have an increased internal resistance and perform worse.