two questions about .ts files

[anctop]

Hello,

I'd like to ask a couple of questions about .ts files.

I've downloaded a sequence of .ts files from an audio stream, and each .ts contains 10 seconds of contents.
I notice that the sizes of the downloaded .ts are not uniform. The "normal" size is 87420B each, but the size of every 5th one is only 87232B. For example, a sequence of files named from "file_3.ts" to "file_15.ts", the sizes of "file_4.ts", "file_9.ts" and "file_14.ts" are 87232B but the rest are 87420B large.
The files seem to be intact, but I'm curious about the pattern of file sizes. Is this normal ?

Next I concatenate the .ts files to a single .mp3 file using FFmpeg. The resultant .mp3 is then played with FFplay.
I notice that when a "jump" or noise is heard in the playback, some error lines appear :

  Duration: 00:06:40.32, start: 0.016531, bitrate: 64 kb/s
    Stream #0:0: Audio: mp3, 32000 Hz, stereo, s16p, 64 kb/s
    Metadata:
      encoder         : Lavf
[mp3 @ 02fc7ac0] overread, skip -5 enddists: -3 -3
[mp3 @ 02fc7ac0] overread, skip -5 enddists: -4 -4
  12.37 M-A:  0.000 fd=   0 aq=    2KB vq=    0KB sq=    0B f=0/0

This probably indicates some imperfection in the file. It would be ideal to check the entire .mp3 with FFplay, but obviously not an efficient way.
I wonder if there is a fast tool for such integrity check without real-time playback ?