Help- I broke something and cannot figure it out re: Adafruit Wave Shield

The attached code was working perfectly and then it stopped playing the music. I had added a couple variables and some code inside the loop(). Even thought the IDE said SRAM was 1785 out of 2000 (UNO) I thought I might have gone over the limit so I commented out the changes and reduced the SRAM but it still didn't work. If I load the daphc example from the WaveHC library, it plays all of the sound files perfectly. With my code, I now get a consistent "Couldn't open file kids2.wav" or any other file I try. To the best of my knowledge I haven't touched the WaveHC code. Can anyone see the discrepancy? I'm 70 and need all the help I can get.

//  this is the "final" test version that is working well. remote can trigger a song.

//                slave 3        slave 3

//#include <FatReader.h>
//#include <SdReader.h>
//#include <avr/pgmspace.h>
#include "WaveUtil.h"
#include "WaveHC.h"
#include <Wire.h>

SdReader card;    // This object holds the information for the card
FatVolume vol;    // This holds the information for the partition on the card
FatReader root;   // This holds the information for the filesystem on the card
FatReader f;      // This holds the information for the file we're play

WaveHC wave;      // This is the only wave (audio) object, since we will only play one at a time

//***********  I2C  variables  *************
byte cb[100];   // [0] to [49] are incoming from master, [50] to [99] are outgoing to master
byte cbb[25];
byte cbsend[25];
byte tled=A0;
byte rled=A1;
int swt=0;
int swr=0;
int insw=0;
int outsw=0;
byte slavenum=3;
byte jsw=0;
//**************end I2C variables  *****************
//***********  I2C  variables definitions *************
byte& mode=cb[0];  
byte& function=cb[1];
byte& action=cb[2];
byte& sysmode=cb[3];
byte& perfmode=cb[4];
byte& testmode=cb[5];
byte& songnum=cb[10];// index # of song to be played


//**************end I2C variables definitions *****************
//*****************  system variables  **********************
	byte oldaction=0;
	byte oldsongnum=0;
	byte song=0;
//******************* end system variables  *****************************

//this handy function will return the number of bytes currently free in RAM, great for debugging!   
// int freeRam(void)
// {
  // extern int  __bss_end; 
  // extern int  *__brkval; 
  // int free_memory; 
  // if((int)__brkval == 0) {
    // free_memory = ((int)&free_memory) - ((int)&__bss_end); 
  // }
  // else {
    // free_memory = ((int)&free_memory) - ((int)__brkval); 
  // }
  // return free_memory; 
// } 

void sdErrorCheck(void)
{
  if (!card.errorCode()) return;
  putstring("\n\rSD I/O error: ");
  Serial.print(card.errorCode(), HEX);
  putstring(", ");
  Serial.println(card.errorData(), HEX);
  while(1);
}
//********************   begin SETUP  *******************************
void setup() {
  // set up serial port
  Serial.begin(57600);
  
 //  putstring("Free RAM: ");       // This can help with debugging, running out of RAM is bad
 // Serial.println(freeRam());      // if this is under 150 bytes it may spell trouble!
  
  // Set the output pins for the DAC control. This pins are defined in the library
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(tled, OUTPUT);
  pinMode(rled, OUTPUT);
    Wire.begin(slavenum);
    Wire.onReceive(cbin);
    Wire.onRequest(cbout);
    for(int jk=0;jk<=24;jk++)cbb[jk]=0;
    
    for(int jj=0;jj<=99;jj++)
    {
      cb[jj]=0;
    }
    cb[74]=24;
    cb[99]=49;
    for (int jj=0;jj<=24;jj++)
    {
      cbsend[jj]=0;
    }
    digitalWrite(rled,LOW);
	digitalWrite(tled,LOW);
//************** end I2C setup  ************************
 
 
  //  if (!card.init(true)) { //play with 4 MHz spi if 8MHz isn't working for you
  if (!card.init()) {         //play with 8 MHz spi (default faster!)  
    putstring_nl("Card init. failed!");  // Something went wrong, lets print out why
    sdErrorCheck();
    while(1);                            // then 'halt' - do nothing!
  }
  
  // enable optimize read - some cards may timeout. Disable if you're having problems
  card.partialBlockRead(true);
 
// Now we will look for a FAT partition!
  uint8_t part;
  for (part = 0; part < 5; part++) {     // we have up to 5 slots to look in
    if (vol.init(card, part)) 
      break;                             // we found one, lets bail
  }
  if (part == 5) {                       // if we ended up not finding one  :(
    putstring_nl("No valid FAT partition!");
    sdErrorCheck();      // Something went wrong, lets print out why
    while(1);                            // then 'halt' - do nothing!
  }
  
  // Lets tell the user about what we found
  putstring("Using partition ");
  Serial.print(part, DEC);
  putstring(", type is FAT");
  Serial.println(vol.fatType(),DEC);     // FAT16 or FAT32?
  
  // Try to open the root directory
  if (!root.openRoot(vol)) {
    putstring_nl("Can't open root dir!"); // Something went wrong,
    while(1);                             // then 'halt' - do nothing!
  }
  
  // Whew! We got past the tough parts.
  putstring_nl("Ready!");
}
//**************************  end SETUP  ******************************
//**********************  loop begins  *******************************
void loop() {
	// Serial.print(mode);
	// Serial.print("  ");
	// Serial.print(function);
	// Serial.print("  ");
	// Serial.print(action);
	// Serial.print("  ");
	// Serial.print(sysmode);
	// Serial.print("  ");
	// Serial.print(perfmode);
	// Serial.print("  ");
	// Serial.print(testmode);
	// Serial.print("  ");
	// Serial.println(songnum);
	sysmode=2;
	songnum=3;
  switch(sysmode){
	case 1:
		wave.stop();
	break;
	case 2:
		 if(songnum == 0){wave.stop(); return;}
		 if(songnum != 0){
			if(songnum == 99) {wave.stop(); return;}
			if(songnum == oldsongnum && wave.isplaying)return;
			if(songnum != oldsongnum){
				wave.stop(); 
				oldsongnum=songnum;
				//Serial.print("songnum = ");
				//Serial.println(songnum);
				switch (songnum) {
					case 1:
						playfile("atmos.wav");
					break;
					case 2:
						playfile("melbel.wav");
					break;
					case 3:
						playfile("kids2.wav");
					break;
					case 4:
						playfile("kids3.wav");
					break;
					case 5:
						playfile("spacy1.wav");
					break;
					case 6:
						playfile("mspolly.WAV");
					break;
				}
		   }
		 }
	break;
	case 3:
		if(mode == 2 && function == 4) {
        	if(action==0)return; 
        	if(action==99) {wave.stop(); return; }
        	if(action==oldaction && wave.isplaying) return;
        	if(action != oldaction) {
        		wave.stop(); 
        		oldaction=action;
        		// Serial.print("action - ");
				// Serial.println(action);	
				switch (action) {
					case 1:
						playfile("atmos.wav");
					break;
					case 2:
						playfile("melbel.wav");
					break;
					case 3:
						playfile("kids2.wav");
					break;
					case 4:
						playfile("kids3.wav");
					break;
					case 5:
						playfile("spacy1.wav");
					break;
					case 6:
						playfile("mspolly.WAV");
					break;
				}
		}
	}
	break;
  }
  delay(500);
}
//********************  loop ends   *****************************************

// Plays a full file from beginning to end with no pause.
void playcomplete(char *name) {
  // call our helper to find and play this name
  playfile(name);
  while (wave.isplaying) {
  // do nothing while its playing
  }
  // now its done playing
}

void playfile(char *name) {
  // see if the wave object is currently doing something
  if (wave.isplaying) {// already playing something, so stop it!
    wave.stop(); // stop it
  }
  // look in the root directory and open the file
  if (!f.open(root, name)) {
    putstring("Couldn't open file "); Serial.print(name); return;
  }
  // OK read the file and turn it into a wave object
  if (!wave.create(f)) {
    putstring_nl("Not a valid WAV"); return;
  }
  
  // ok time to play! start playback
  wave.play();
}
//****IN ******* IN *****************
void cbin (int x){ 
if(swr==0)digitalWrite(rled,HIGH);
for(int jj=0;jj<=24;jj++)cbb[jj]=Wire.read();
for(int jj=0;jj<=24;jj++)cb[(cbb[24]-24)+jj]= cbb[jj]; 
if(swr==5)digitalWrite(rled,LOW);
if(swr==8)swr=-1;
swr++;
}
//************** end IN  ***************************
//*****OUT*********OUT****************
void cbout(){
if(swt==0)digitalWrite(tled,HIGH);
if(outsw==2)outsw=0;
for(int jj=0;jj<=24;jj++)cbsend[jj]= cb[jj+50+(outsw*25)];
Wire.write(cbsend,25);
outsw++;
if(swt==5)digitalWrite(tled,LOW);
if(swt==8)swt=-1;
swt++;
}
//******************* end OUT  *********************