iphone - RemoteIO Audio Problem - simulator = good - device= bad -

o.k , i'm using core audio extract audio 10 different sample sources , mixing them in callback function.

it works perfect in simulator , well. ran trouble when tried run on 4.2 iphone device.

if mix 2 audio files in callback ok. if mix 5 or 6 audio files audio plays after short amount of time audio degrades , no audio go speakers. (the callback not stop).

if try mix 10 audio files callback runs no audio @ comes out.

it's callback running out of time might explain case mix 5 or 6 not explain last case mixing 10 audio sources no audio @ played.

i'm not sure if following has bearing message prints console when i'm debugging. indication problem is?

mem 0x1000 0x3fffffff cache mem 0x40000000 0xffffffff none mem 0x00000000 0x0fff none run running… [switching thread 11523] [switching thread 11523] re-enabling shared library breakpoint 1 continue warning: unable read symbols /developer/platforms/iphoneos.platform/devicesupport/4.2.1 (8c148)/symbols/usr/lib/info/dns.so (file not found). 

** set callback**

#pragma mark - #pragma mark callback setup & control  - (void) setupcallback  {     osstatus status;       // describe audio component     audiocomponentdescription desc;     desc.componenttype = kaudiounittype_output;     desc.componentsubtype = kaudiounitsubtype_remoteio;     desc.componentflags = 0;     desc.componentflagsmask = 0;     desc.componentmanufacturer = kaudiounitmanufacturer_apple;      // component     audiocomponent inputcomponent = audiocomponentfindnext(null, &desc);      // audio units     status = audiocomponentinstancenew(inputcomponent, &audiounit);      uint32 flag = 1;     // enable io playback     status = audiounitsetproperty(audiounit,                                    kaudiooutputunitproperty_enableio,                                    kaudiounitscope_output,                                    koutputbus,                                   &flag,                                    sizeof(flag));      //apply format     status = audiounitsetproperty(audiounit,                                    kaudiounitproperty_streamformat,                                    kaudiounitscope_input,                                    koutputbus,                                    &stereostreamformat,                                    sizeof(stereostreamformat));      // set playback  callback     aurendercallbackstruct callbackstruct;     callbackstruct.inputproc = playbackcallback; //!!****assignment incompatible pointer warning here *****!!!!!!     //set reference "self" becomes *inrefcon in playback callback     callbackstruct.inputprocrefcon = self;      status = audiounitsetproperty(audiounit,                                    kaudiounitproperty_setrendercallback,                                    kaudiounitscope_global,                                    koutputbus,                                   &callbackstruct,                                    sizeof(callbackstruct));      // initialise     status = audiounitinitialize(audiounit); // error check status   } 

the callback

static osstatus playbackcallback (                                       void                        *inrefcon,      // pointer struct containing complete audio data                                       //    play, state information such                                        //    first sample play on invocation of callback.                                      audiounitrenderactionflags  *ioactionflags, // unused here. when generating audio, use ioactionflags indicate silence                                       //    between sounds; silence, memset iodata buffers 0.                                       audiotimestamp        *intimestamp,   // unused here.                                      uint32                      inbusnumber,    // mixer unit input bus requesting new                                      //        frames of audio data play.                                      uint32                      innumberframes, // number of frames of audio provide buffer(s)                                      //        pointed iodata parameter.                                      audiobufferlist             *iodata         // on output, audio data play. callback's primary                                       //        responsibility fill buffer(s) in                                       //        audiobufferlist.                                      ) {       engine *remoteioplayer = (engine *)inrefcon;     audiounitsampletype *outsampleschannelleft;     audiounitsampletype *outsampleschannelright;      outsampleschannelleft                 = (audiounitsampletype *) iodata->mbuffers[0].mdata;      outsampleschannelright  = (audiounitsampletype *) iodata->mbuffers[1].mdata;      int thetime =0;     thetime=remoteioplayer.sampletime;           (int framenumber = 0; framenumber < innumberframes; ++framenumber)         {             // nextpacket returns 32 bit value, 1 frame.             audiounitsampletype *suml=0;             audiounitsampletype *sumr=0;              //nslog (@"frame number -  %i", framenumber);             for(int j=0;j<10;j++)              {                   audiounitsampletype valuetoaddl=0;                 audiounitsampletype valuetoaddr=0;                   //valuetoadd = [remoteioplayer getsample:j ];                 valuetoaddl = [remoteioplayer getnoninterleavedsample:j currenttime:thetime channel:0 ];                 //valuetoaddl = [remoteioplayer getsample:j];                 valuetoaddr = [remoteioplayer getnoninterleavedsample:j currenttime:thetime channel:1 ];                  suml = suml+(valuetoaddl/10);                 sumr = sumr+(valuetoaddr/10);              }               outsampleschannelleft[framenumber]=(audiounitsampletype) suml;             outsampleschannelright[framenumber]=(audiounitsampletype) sumr;               remoteioplayer.sampletime +=1;           }      return noerr; } 

my audio fetching function

-(audiounitsampletype) getnoninterleavedsample:(int) index currenttime:(int)time channel:(int)ch;  {      audiounitsampletype returnvalue= 0;      soundstruct snd=soundstructarray[index];         uint64 sn= snd.framecount;       uint64 st=sampletime;     uint64 read= (uint64)(st%sn);       if(ch==0)     {         if (snd.sendvalue==1) {             returnvalue = snd.audiodataleft[read];          }else {             returnvalue=0;         }      }else if(ch==1)      {         if (snd.sendvalue==1) {         returnvalue = snd.audiodataright[read];         }else {             returnvalue=0;         }          soundstructarray[index].samplenumber=read;     }       if(soundstructarray[index].samplenumber >soundstructarray[index].framecount)     {         soundstructarray[index].samplenumber=0;      }      return returnvalue;   } 

edit 1

in response @andre changed callback following still did not help.

static osstatus playbackcallback (                                       void                        *inrefcon,      // pointer struct containing complete audio data                                       //    play, state information such                                        //    first sample play on invocation of callback.                                      audiounitrenderactionflags  *ioactionflags, // unused here. when generating audio, use ioactionflags indicate silence                                       //    between sounds; silence, memset iodata buffers 0.                                       audiotimestamp        *intimestamp,   // unused here.                                      uint32                      inbusnumber,    // mixer unit input bus requesting new                                      //        frames of audio data play.                                      uint32                      innumberframes, // number of frames of audio provide buffer(s)                                      //        pointed iodata parameter.                                      audiobufferlist             *iodata         // on output, audio data play. callback's primary                                       //        responsibility fill buffer(s) in                                       //        audiobufferlist.                                      ) {       engine *remoteioplayer = (engine *)inrefcon;     audiounitsampletype *outsampleschannelleft;     audiounitsampletype *outsampleschannelright;      outsampleschannelleft                 = (audiounitsampletype *) iodata->mbuffers[0].mdata;      outsampleschannelright  = (audiounitsampletype *) iodata->mbuffers[1].mdata;      int thetime =0;     thetime=remoteioplayer.sampletime;           (int framenumber = 0; framenumber < innumberframes; ++framenumber)         {             // nextpacket returns 32 bit value, 1 frame.             audiounitsampletype suml=0;             audiounitsampletype sumr=0;              //nslog (@"frame number -  %i", framenumber);             for(int j=0;j<16;j++)              {                    soundstruct snd=remoteioplayer->soundstructarray[j];                 uint64 sn= snd.framecount;                   uint64 st=remoteioplayer.sampletime;                 uint64 read= (uint64)(st%sn);                  suml+=  snd.audiodataleft[read];                 suml+= snd.audiodataright[read];               }               outsampleschannelleft[framenumber]=(audiounitsampletype) suml;             outsampleschannelright[framenumber]=(audiounitsampletype) sumr;               remoteioplayer.sampletime +=1;           }      return noerr; } 

1. like andre said, it's best not have objective-c function calls in callback. should change inputprocrefcon c-struct instead of objective-c object.

2. also, looks might going frame-by-frame 'manually' copying data buffer. instead, use memcopy copy chunk of data in.

3. also, i'm pretty sure you're not doing disk i/o in callback, if you shouldn't either.