Arduino Nano v3: is it possible to PCM + AltSoftSerial? I wonder is it possible to change PCM.h 's lib use of 16-bit timer1 to another 8-bit?
Now I'm getting 

libraries\AltSoftSerial\AltSoftSerial.cpp.o (symbol from plugin): In function `AltSoftSerial::read()':

(.text+0x0): multiple definition of `__vector_11'

libraries\PCM\PCM.c.o (symbol from plugin):(.text+0x0): first defined here

collect2.exe: error: ld returned 1 exit status

exit status 1


when compiling

#include &lt;PCM.h&gt;
#include &lt;AltSoftSerial.h&gt;


An attempt to avoid XY problem: make AltSoftSerial work alongside with PCM-alike library on Arduino Nano v3 without SD. 

I'm poorly familiar with timers and interrupts, so I'll be very grateful for any advice and suggestion!
It is not easy to make PCM sounds with the Arduino Uno or Nano. A few libraries can do that, but they use two timers: Timer1 and Timer2. Timer0 is already in use by Arduino. When using those libraries, the Arduino Nano is almost completely occupied to make sounds.

A software serial port also requires a lot from the Arduino Nano. The AltSoftSerial uses Timer1.

Those two will never work together. It is not possible.
For what do you need the serial port ?
Could that be done in a different way ?

The normal SoftwareSerial does not use a timer, but because it also occupies the Arduino Nano a lot, using SoftwareSerial together with a PCM sound at the same time will not work. Perhaps if you carefully design the sketch and never use them at the same time, it might work. I doubt if it will be reliable.

A better option is to swap the Arduino Nano for an Arduino Micro. Then you have a extra hardware serial port and you don't need the AltSoftSerial anymore. The library to make PCM sounds has to be compatible with the Arduino Micro. I suppose that not every PCM library is compatible.

The best option is to use a MP3 shield. Then you can send a command to play a MP3 sound. If you use a MP3 shield with a Arduino Micro or Arduino Leonardo or Arduino Mega 2560 or Arduino Zero or Arduino Due, then you have a extra hardware serial port and you don't need libraries that occupy the most of the Arduino board, and your sketch will be a normal sketch that does normal things.