Rav Elyashiv will reportedly ban the MP4

Via the Yeshiva World:

According to the weekly Belz-affiliated BaKehilla newspaper, HaGaon Rav Yosef Sholom Elyashiv is going to comply with the growing number of requests from rabbonim and roshei yeshiva and will be prohibiting MP4 players.

Roshei yeshiva visited Maran this week, and one case that was shared was a bachor who he noticed was totally engulfed in the gemora, swaying back-and-forth rhythmically as he stared at the sefer, prompting the rav to go over to his talmid to experience the event. It was then that he noticed the bachor was swaying to the music and not his gemora, hooked into his MP4 player which was well hidden.

The report adds that seminary rabbonim concur, fearing many good students may be corrupted by the influence.

When Maran asked “what can I do?” he was requested to publish a letter prohibiting the device.

Rav Elyashiv asked, “The tzibur still pays attention to such letters?” to which they responded the letter lends credibility to their statements that the players are problematic. It also gives rabbonim in yeshivas and seminaries the authority to send students home if found with the “portable TV units”.

Rav Elyashiv indicated a letter would be released, a letter that other Gedolei Yisrael will also sign, but it is unclear if the letter will be directed to talmidim and talmidos, or a general ban on the device.

(Yechiel Spira - YWN Israel)

Of note is Rav Elyashiv's response: The tzibur still pays attention to such letters?

I would read this as a partial realization that the ban after ban after ban, and the flood of letters for causes citing Gedolim undermines the general effectiveness of such letters.

And all this on the basis of one "persuasive" case? I would guess that even if there were not video capability of an MP4 (whose video capabilities it does not seem he was using), he could still sway to the music with an MP3, or a tape player.

I remember from high school, though I did not have a Walkman, some other kids did. And my rebbe, or perhaps it was the school, made a policy that you could not listen to a Walkman on school premises. I think there was an exception if it was during recess and the tape was a kosher one. But this is the responsibility of a high school or elementary school rebbe or principal, not the Gadol HaDor. Askanim, stop harrassing Rav Elyashiv with your minor requests!

As Yisro advised his son-in-law:

יז וַיֹּאמֶר חֹתֵן מֹשֶׁה, אֵלָיו: לֹא-טוֹב, הַדָּבָר, אֲשֶׁר אַתָּה, עֹשֶׂה.	17 And Moses' father-in-law said unto him: 'The thing that thou doest is not good.
יח נָבֹל תִּבֹּל--גַּם-אַתָּה, גַּם-הָעָם הַזֶּה אֲשֶׁר עִמָּךְ: כִּי-כָבֵד מִמְּךָ הַדָּבָר, לֹא-תוּכַל עֲשֹׂהוּ לְבַדֶּךָ.	18 Thou wilt surely wear away, both thou, and this people that is with thee; for the thing is too heavy for thee; thou art not able to perform it thyself alone.

and then

כב וְשָׁפְטוּ אֶת-הָעָם, בְּכָל-עֵת, וְהָיָה כָּל-הַדָּבָר הַגָּדֹל יָבִיאוּ אֵלֶיךָ, וְכָל-הַדָּבָר הַקָּטֹן יִשְׁפְּטוּ-הֵם; וְהָקֵל, מֵעָלֶיךָ, וְנָשְׂאוּ, אִתָּךְ.

22 And let them judge the people at all seasons; and it shall be, that every great matter they shall bring unto thee, but every small matter they shall judge themselves; so shall they make it easier for thee and bear the burden with thee.

Not every school matter needs to be brought before the Gadol Hador. They should learn to respect their rebbe and their school administration.

There is a further problem. If a school wants to set up a policy, they are free to go ahead and do so. But different schools might have different philosophies towards this. If you get the Gadol to sign a letter about this, it is likely going to be applied across the board, or taken by askanim to apply across the board. And as noted in the article:

Rav Elyashiv indicated a letter would be released, a letter that other Gedolei Yisrael will also sign, but it is unclear if the letter will be directed to talmidim and talmidos, or a general ban on the device

I would guess that regardless of Rav Elyashiv's intent (and he does not know anything about the prevalence of these devices and how they are typically used), this will be part of a game plan of banning the device in general.