ALSA not working properly: aplay: pcm_write:1939: write erro

[Karloch]

I'm setting up my Raspberry Pi 3B to play several sounds on determinate events through a speaker connected to the analog 3'5mm output (already forced 3'5mm output through raspi-config and it sounds OK). After the Raspbian boots, sounds works like a charm, but after several plays using aplay it will stop working and return the following error:

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user@raspi:~$ aplay cartoon001.wav
Playing WAVE 'cartoon001.wav' : Signed 16 bit Little Endian, Rate 11025 Hz, Mono
aplay: pcm_write:1939: write error: Input/output error

It will only work again after a restart, repeating the symptoms. Playing the sound as root gives same result.

Several data from my setup:

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user@raspi:~$ uname -a
Linux raspi 4.4.13-v7+ #894 SMP Mon Jun 13 13:13:27 BST 2016 armv7l GNU/Linux

user@raspi:~$ aplay -L
null
    Discard all samples (playback) or generate zero samples (capture)
default:CARD=ALSA
    bcm2835 ALSA, bcm2835 ALSA
    Default Audio Device
sysdefault:CARD=ALSA
    bcm2835 ALSA, bcm2835 ALSA
    Default Audio Device
dmix:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct sample mixing device
dmix:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct sample mixing device
dsnoop:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct sample snooping device
dsnoop:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct sample snooping device
hw:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct hardware device without any conversions
hw:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct hardware device without any conversions
plughw:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Hardware device with all software conversions
plughw:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Hardware device with all software conversions

user@raspi:~$ lsmod
Module                  Size  Used by
xt_multiport            1756  1
iptable_filter          1409  1
ip_tables              11637  1 iptable_filter
x_tables               12507  3 ip_tables,xt_multiport,iptable_filter
arc4                    1958  0
ecb                     2127  0
md4                     3615  0
md5                     2039  1
hmac                    2959  1
nls_utf8                1318  1
cifs                  382801  2
bnep                   10340  2
hci_uart               17943  1
btbcm                   5929  1 hci_uart
bluetooth             326105  22 bnep,btbcm,hci_uart
brcmfmac              186343  0
brcmutil                5661  1 brcmfmac
cfg80211              427855  1 brcmfmac
rfkill                 16037  4 cfg80211,bluetooth
snd_bcm2835            20511  0
snd_pcm                75698  1 snd_bcm2835
snd_timer              19160  1 snd_pcm
snd                    51844  3 snd_bcm2835,snd_timer,snd_pcm
bcm2835_gpiomem         3040  0
spi_bcm2835             7286  0
bcm2835_wdt             3225  0
uio_pdrv_genirq         3164  0
uio                     8000  1 uio_pdrv_genirq
ipv6                  347530  34

user@raspi:~$ amixer
Simple mixer control 'PCM',0
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined
  Playback channels: Mono
  Limits: Playback -10239 - 400
  Mono: Playback 400 [100%] [4.00dB] [on]

[sash_b]

Hi Karloch,

I am seeing the same issue.
Did you get over this issue yet?

[Karloch]

I'm afraid not, I keep with the same problem

[flatmax]

Can you rmmod and modprobe the snd_bcm2835 module ?
Does the sound come back ?

Matt

[Karloch]

Same result:

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~$ sudo rmmod snd_bcm2835
~$ sudo modprobe snd_bcm2835
~$ aplay cartoon001.wav
Playing WAVE 'cartoon001.wav' : Signed 16 bit Little Endian, Rate 11025 Hz, Mono
aplay: pcm_write:1939: write error: Error de entrada/salida

[hal8000]

When sound stops anything unusual in system log?

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dmesg | tail -n 10

[Karloch]

Nothing is reported to the kernel log when the error happens:

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~$ dmesg | tail -n 10
[   13.990801] Bluetooth: HCI UART protocol BCM registered
[   14.235080] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[   14.235100] Bluetooth: BNEP filters: protocol multicast
[   14.235125] Bluetooth: BNEP socket layer initialized
[   15.950226] FS-Cache: Netfs 'cifs' registered for caching
[   15.950978] Key type cifs.spnego registered
[   15.951038] Key type cifs.idmap registered
[   16.375080] systemd-journald[134]: Received request to flush runtime journal from PID 1
[   16.725662] Adding 102396k swap on /var/swap.  Priority:-1 extents:3 across:200700k SSFS
[   21.055153] ip_tables: (C) 2000-2006 Netfilter Core Team

[marvinsuess]

Hey,

I have the same problem with my RPi 3B. Maybe there is something wrong with the PWM.

My original problem was that I couldn't write the data for my Neopixel WS2812b LED strip which is usually done via PWM on a GPIO Pin. It worked a while but suddenly it just wrote garbage data (without changes in my code). I tested a different strip, different cables and so on and now I think it has to be something wrong with the PWM. I googled and found that audio is also using PWM so I tried to play audio. I get silence and the same errors as you do:

If I use mpg123:

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[...]

[alsa.c:230] error: Fatal problem with alsa output, error -5.

[audio.c:614] error: Error in writing audio (Input/output error?)!

[mpg123.c:681] error: Deep trouble! Cannot flush to my output anymore!

If I try aplay:

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aplay: pcm_write:1939: Schreibfehler: Eingabe-/Ausgabefehler

Also nothing interesting in syslog.

So maybe you can test the PWM on your Raspberry?

It will be interesting to see if we share the same problem or not.

[Karloch]

So maybe you can test the PWM on your Raspberry?

That's really interesting because I'm using PWM via GPIO in order to perform some beeping through a PC Speaker. Maybe this has something to do with the ALSA failing to play sound?

[rpdom]

So maybe you can test the PWM on your Raspberry?

That's really interesting because I'm using PWM via GPIO in order to perform some beeping through a PC Speaker. Maybe this has something to do with the ALSA failing to play sound?

You can't use hardware PWM via GPIO at the same time as audio via the A/V jack. Analogue audio uses both of the hardware PWM channels.

[marvinsuess]

You can't use hardware PWM via GPIO at the same time as audio via the A/V jack. Analogue audio uses both of the hardware PWM channels.

This is what I found out before I had the problem I described above. I tried to play music while sending data to my LED strip. What I saw was that the LEDs were not doing what I told them to do but showing some random colours somehow in sync with the music. Even when I turned off the music the effect of just showing random colours remained. At this time I became aware that the PWM channels are also used for audio. But I was able to fix it every time I tried by turning the Raspberry off and on again (and if I had read the original post carefully enough I would have seen that this is what Karloch wrote).

So my situation is different. I didn't play music when my current problem first occurred, I just sent data to the LED strip. And the turn-off-and-on-fix doesn't work anymore This and the disability to play music lead me to the conclusion that the PWM may be broken in some way.

Edit: I solved my problem by simply not loading the snd_bcm2835 module. Just go to /etc/modprobe.d and create a file "alsa-blacklist.conf" (with sudo) containing just the line "blacklist snd_bcm2835". Reboot the Raspberry and the problem is gone. I know this doesn't solve Karloch's problem or the problems of anyone who needs sound but I wrote this anyway because someone with the same problem as me may find this post and I don't want to hide the solution.

[jefferson_palheta]

did someone get some solution? I get the same problem because I'm using PWM to control IR transmitter so I can play my sound with sox (play my_song.wav) and it works well but when a run my code that uses pwm then the sound stop and doesn't come back until I restart my RP3.