errors occur when extracting feature

Hi,
I am using egs/sprakbanken_swe/s5 to train model, when comes to command **_steps/make_mfcc.sh --nj 1 --cmd utils/parallel/run.pl data/test exp/make_mfcc/test mfcc_**, the job failed, and the LOG shows:

`Usage: sph2pipe [-h hdr] [-t|-s b:e] [-c 1|2] [-p|-u|-a] [-f typ] infile [outfile]

default conditions (for 'sph2pipe infile'):
* input file contains sphere header
* output full duration of input file
* output all channels from input file
* output same sample coding as input file
* output format is WAV on Wintel machines, SPH elsewhere
* output is written to stdout

optional controls (items bracketed separately above can be combined):
-h hdr -- treat infile as headerless, get sphere info from file 'hdr'
-t b:e -- output portion between b and e sec (floating point)
-s b:e -- output portion between b and e samples (integer)
-c 1 -- only output first channel
-c 2 -- only output second channel
-p -- force conversion to 16-bit linear pcm
-u -- force conversion to 8-bit ulaw
-a -- force conversion to 8-bit alaw
-f typ -- select alternate output header format 'typ'
five types: sph, raw, au, rif(wav), aif(mac)
ERROR (compute-mfcc-feats[5.5.650~4-d9dc2]:Read4ByteTag():wave-reader.cc:56) WaveData: expected 4-byte chunk-name, got read error

[ Stack-Trace: ]
/mnt/e/kaldi/src/lib/libkaldi-base.so(kaldi::MessageLogger::LogMessage() const+0xb42) [0x7f1f2aee6682]
compute-mfcc-feats(kaldi::MessageLogger::LogAndThrow::operator=(kaldi::MessageLogger const&)+0x21) [0x7f1f2bc1520d]
/mnt/e/kaldi/src/lib/libkaldi-feat.so(kaldi::WaveInfo::Read(std::istream&)+0x1c8) [0x7f1f2b5e479e]
/mnt/e/kaldi/src/lib/libkaldi-feat.so(kaldi::WaveData::Read(std::istream&)+0x4e) [0x7f1f2b5e6618]
compute-mfcc-feats(kaldi::WaveHolder::Read(std::istream&)+0x20) [0x7f1f2bc1b846]
compute-mfcc-feats(kaldi::SequentialTableReaderScriptImpl::EnsureObjectLoaded()+0x173) [0x7f1f2bc2324b]
compute-mfcc-feats(kaldi::SequentialTableReaderScriptImpl::Next()+0x27) [0x7f1f2bc23b91]
compute-mfcc-feats(kaldi::SequentialTableReaderScriptImpl::Open(std::__cxx11::basic_string, std::allocator > const&)+0xac) [0x7f1f2bc1862c]
compute-mfcc-feats(kaldi::SequentialTableReader::Open(std::__cxx11::basic_string, std::allocator > const&)+0x1f1) [0x7f1f2bc1bff7]
compute-mfcc-feats(kaldi::SequentialTableReader::SequentialTableReader(std::__cxx11::basic_string, std::allocator > const&)+0x68) [0x7f1f2bc1c352]
compute-mfcc-feats(main+0x845) [0x7f1f2bc1269f]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7) [0x7f1f2a331b97]
compute-mfcc-feats(_start+0x2a) [0x7f1f2bc11d7a]

WARNING (compute-mfcc-feats[5.5.650~4-d9dc2]:Read():feat/wave-reader.h:197) Exception caught in WaveHolder::Read(). kaldi::KaldiFatalError
WARNING (compute-mfcc-feats[5.5.650~4-d9dc2]:EnsureObjectLoaded():util/kaldi-table-inl.h:317) Failed to load object from '/mnt/e/kaldi/egs/sprakbanken_swe/s5/../../../tools/sph2pipe_v2.5/sph2pipe -c 1 -p -f wav /mnt/e/kaldi/egs/sprakbanken_swe/s5/data/local/data/download/0468/0468 sv test/Stasjon18/180100/adb_0468/speech/scr0468/18/04681801/r4680017/u0017010.wav |'
WARNING (compute-mfcc-feats[5.5.650~4-d9dc2]:Close():kaldi-io.cc:515) Pipe /mnt/e/kaldi/egs/sprakbanken_swe/s5/../../../tools/sph2pipe_v2.5/sph2pipe -c 1 -p -f wav /mnt/e/kaldi/egs/sprakbanken_swe/s5/data/local/data/download/0468/0468 sv test/Stasjon18/180100/adb_0468/speech/scr0468/18/04681801/r4680017/u0017010.wav | had nonzero return status 256`

the wav file mentioned in the warning message is exist.
Anyone have any idea about this error?
Thank you!

Start by rerunning the reported steps/make_mfcc.sh command in egs/sprakbanken_swe/s5 and inspect the referenced WAV path and sph2pipe invocation. Read the compute-mfcc-feats and WaveData error output to determine why the pipe does not produce readable WAV data. Done means the failure is reproducible and has a documented diagnosis or verified fix.

Written by the indexing model from the issue text.