Why muTect Error?

Question

[naruto1nrt]

When I use muTect to call somatic SNVs, I got this error:

INFO  10:05:12,111 ProgressMeter -       1:1249156        3.86e+05   51.1 s        2.2 m      0.1%        12.7 h    12.7 h 
INFO  10:05:13,434 MuTect - [MUTECTOR] Processed 21006455 reads in 23342 ms 
INFO  10:05:14,428 MuTect - [MUTECTOR] Processed 22006618 reads in 994 ms 
INFO  10:05:15,285 MuTect - [MUTECTOR] Processed 23007043 reads in 857 ms 
INFO  10:05:16,698 MuTect - [MUTECTOR] Processed 24007132 reads in 1412 ms 
INFO  10:05:17,538 MuTect - [MUTECTOR] Processed 25007397 reads in 841 ms 
INFO  10:05:18,322 MuTect - [MUTECTOR] Processed 26007462 reads in 784 ms 
INFO  10:05:20,498 MuTect - [MUTECTOR] Processed 27007872 reads in 2176 ms 
INFO  10:05:21,391 MuTect - [MUTECTOR] Processed 28008020 reads in 893 ms 
Error processing 1:1425816
java.lang.IllegalArgumentException: Comparison method violates its general contract!
        at java.util.TimSort.mergeLo(Unknown Source)
        at java.util.TimSort.mergeAt(Unknown Source)
        at java.util.TimSort.mergeForceCollapse(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.Arrays.sort(Unknown Source)
        at java.util.Collections.sort(Unknown Source)
        at org.broadinstitute.cga.tools.gatk.walkers.cancer.mutect.MuTect.map(MuTect.java:480)
        at org.broadinstitute.cga.tools.gatk.walkers.cancer.mutect.MuTect.map(MuTect.java:34)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano$TraverseLociMap.apply(TraverseLociNano.java:243)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano$TraverseLociMap.apply(TraverseLociNano.java:231)
        at org.broadinstitute.sting.utils.nanoScheduler.NanoScheduler.executeSingleThreaded(NanoScheduler.java:287)
        at org.broadinstitute.sting.utils.nanoScheduler.NanoScheduler.execute(NanoScheduler.java:252)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:120)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:67)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:23)
        at org.broadinstitute.sting.gatk.executive.LinearMicroScheduler.execute(LinearMicroScheduler.java:74)
        at org.broadinstitute.sting.gatk.GenomeAnalysisEngine.execute(GenomeAnalysisEngine.java:281)
        at org.broadinstitute.sting.gatk.CommandLineExecutable.execute(CommandLineExecutable.java:113)
        at org.broadinstitute.sting.commandline.CommandLineProgram.start(CommandLineProgram.java:236)
        at org.broadinstitute.sting.commandline.CommandLineProgram.start(CommandLineProgram.java:146)
        at org.broadinstitute.sting.gatk.CommandLineGATK.main(CommandLineGATK.java:93)
WARN  10:05:38,570 RestStorageService - Error Response: PUT '/GATK_Run_Reports/AYB5KWIYqN07noZtss0W0rLJsJKbxV9L.report.xml.gz' -- ResponseCode: 403, ResponseStatus: Forbidden, Request Headers: [Content-Length: 1042, Content-MD5: 0bdVBZA1rXh2fFvP/MmNPA==, Content-Type: application/octet-stream, x-amz-meta-md5-hash: d1b755059035ad78767c5bcffcc98d3c, Date: Sun, 06 Jul 2014 02:05:36 GMT, Authorization: AWS AKIAJXU7VIHBPDW4TDSQ:w+mtipZjxCfoKDW5CZJiLQlydJU=, User-Agent: JetS3t/0.8.1 (Linux/2.6.32-220.13.1.el6.x86_64; amd64; en; JVM 1.7.0_25), Host: s3.amazonaws.com, Expect: 100-continue], Response Headers: [x-amz-request-id: D9E594243C1075C2, x-amz-id-2: cABM436Oq0NZ1uur23AOa0UrGDhGHpQW+AUNZCpBEPCB0YWtUJMMaCPxodGBYaTL, Content-Type: application/xml, Transfer-Encoding: chunked, Date: Sun, 06 Jul 2014 02:04:36 GMT, Connection: close, Server: AmazonS3] 
##### ERROR ------------------------------------------------------------------------------------------
##### ERROR stack trace 
java.lang.RuntimeException: java.lang.IllegalArgumentException: Comparison method violates its general contract!
        at org.broadinstitute.cga.tools.gatk.walkers.cancer.mutect.MuTect.map(MuTect.java:712)
        at org.broadinstitute.cga.tools.gatk.walkers.cancer.mutect.MuTect.map(MuTect.java:34)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano$TraverseLociMap.apply(TraverseLociNano.java:243)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano$TraverseLociMap.apply(TraverseLociNano.java:231)
        at org.broadinstitute.sting.utils.nanoScheduler.NanoScheduler.executeSingleThreaded(NanoScheduler.java:287)
        at org.broadinstitute.sting.utils.nanoScheduler.NanoScheduler.execute(NanoScheduler.java:252)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:120)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:67)
        at org.broadinstitute.sting.gatk.traversals.TraverseLociNano.traverse(TraverseLociNano.java:23)
        at org.broadinstitute.sting.gatk.executive.LinearMicroScheduler.execute(LinearMicroScheduler.java:74)
        at org.broadinstitute.sting.gatk.GenomeAnalysisEngine.execute(GenomeAnalysisEngine.java:281)
        at org.broadinstitute.sting.gatk.CommandLineExecutable.execute(CommandLineExecutable.java:113)
        at org.broadinstitute.sting.commandline.CommandLineProgram.start(CommandLineProgram.java:236)
        at org.broadinstitute.sting.commandline.CommandLineProgram.start(CommandLineProgram.java:146)
        at org.broadinstitute.sting.gatk.CommandLineGATK.main(CommandLineGATK.java:93)
Caused by: java.lang.IllegalArgumentException: Comparison method violates its general contract!
        at java.util.TimSort.mergeLo(Unknown Source)
        at java.util.TimSort.mergeAt(Unknown Source)
        at java.util.TimSort.mergeForceCollapse(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.Arrays.sort(Unknown Source)
        at java.util.Collections.sort(Unknown Source)
        at org.broadinstitute.cga.tools.gatk.walkers.cancer.mutect.MuTect.map(MuTect.java:480)
        ... 14 more
##### ERROR ------------------------------------------------------------------------------------------
##### ERROR A GATK RUNTIME ERROR has occurred (version 2.2-25-g2a68eab):
##### ERROR
##### ERROR Please visit the wiki to see if this is a known problem
##### ERROR If not, please post the error, with stack trace, to the GATK forum
##### ERROR Visit our website and forum for extensive documentation and answers to 
##### ERROR commonly asked questions http://www.broadinstitute.org/gatk
##### ERROR
##### ERROR MESSAGE: java.lang.IllegalArgumentException: Comparison method violates its general contract!
##### ERROR ------------------------------------------------------------------------------------------

who know WHY?

Thanks