Issue with lts function

[Mario Rollo]

Dear all,

I am dealing with an unusual issue with the lts function when using it on a brief series of AudioMoth files. Each file is five minutes long and 28.8MB in size, amounting to a total of 50 minutes. These files all share identical WaveObject parameters: number of samples (14400000), duration (300 seconds), sampling rate (48000 Hz), channels (Mono), PCM (integer format), and bit (16).

Before running the function, I had previously defined the file directory according to the example given in https://rdrr.io/cran/seewave/man/lts.html. 

I then executed the function using this syntax: 

lts(dir, wl = 1024, ovlp = 50, col = spectro.colors(30), fftw = FALSE, verbose = TRUE, ntann = NULL, tlab = "Time(min)", flab = "Frequency (kHz)" , recorder="audiomoth")

The function appeared to process and list the files correctly; however, this error message was displayed in the prompt. 

[1] "File # 1 20191002_210000.wav processed"
[1] "File # 2 20191002_210505.wav processed"
[1] "File # 3 20191002_211010.wav processed"
[1] "File # 4 20191002_211515.wav processed"
[1] "File # 5 20191002_212020.wav processed"
[1] "File # 6 20191002_212525.wav processed"
[1] "File # 7 20191002_213030.wav processed"
[1] "File # 8 20191002_213535.wav processed"
[1] "File # 9 20191002_214040.wav processed"
[1] "File # 10 20191002_214545.wav processed"
[1] "File # 11 20191002_215050.wav processed"
Error in image.default(x = time, xaxt = "n", xlab = "", y = freq, ylab = flab,  :
  'x' and 'y' values must be finite and non-missing

Although I scrutinised all of the parameters used, I was unable to determine the source of the problem.

My system includes R version 4.2.2, RStudio version 2022.12.0+353, seewave version 2.2.0, and mac os ventura 13.2.1.

Thanks in anticipation for your attention,

Best,

Mario