Here is a message posted by Korg:

\Hello all,

We have discovered an unusual problem affecting a very small number of the Sample RAM backup batteries in both models (76 key and 61 key) of the Pa3X, which requires these batteries to be replaced. In certain very extreme conditions, the faulty battery pack may not be protected against accidental short circuits, leading to possible extensive damage to the Pa3X and maybe even surrounding areas. Because the vast majority of batteries are not defective, and because the circumstances required to cause the problem are so extreme, our regular QC tests and outside certification companies only discovered this problem in April 2012. Since we have no way of tracing which Pa3X have the faulty batteries, all the batteries installed in units manufactured before April 2012 must be replaced as a precautionary measure.

To identify whether or not your Pa3X was produced before April 2012, please refer to the list at the end of this message. Please check only the last FOUR (4) digits of the serial number on the back panel of the Pa3X. Any Pa3X that were corrected at the factory will have a sticker affixed, indicating the correct battery is fitted.

Fortunately, changing the battery is easy to do. The Pa3X was designed so that users could easily replace the battery at any time. Instructions for battery replacement are on page 257 of the owner’s manual, and also included in the new battery pack. Because this is done at your own risk, however, it can also be changed by your Korg Pa3X dealer or authorized service center if you are uncomfortable with the procedure. Korg will be dispatching replacement batteries to all distributors in mid-May. Until the replacement batteries are available, we strongly recommend that you remove the existing battery from your Pa3X. Its main purpose is to speed up the start time, and the battery does not affect any other aspect of the performance of the keyboard. With the battery, the Pa3X starts in under a minute. Without the battery, start‐up time is between 2 and 3 minutes, depending upon the amount of USER PCM installed. You can keep performing with and using your Pa3X without the battery.

What you should do:
1. Check the serial number of your Pa3X, and refer to the list below to determine if your Pa3X was produced before April 2012.
2. Remove the battery from your Pa3X according to the instructions on page 257 of your owners’ manual.
3. Please refer to: http://www.korg.co.jp/English/Distributors/index.html, and contact your local distributor to arrange an exchange. For USA-based customers, we will have an online form that can be filled out (this post will be edited with the appropriate information shortly).
5. We will need ALL of the replaced (defective) batteries returned. For USA-based customers, the replacement batteries will include materials for a prepaid return shipment. For customers outside the USA, please contact your local distributor for instructions.

We apologize sincerely for any inconvenience that this will cause, and wish to assure you that the likelihood of any users experiencing a problem is extremely remote.

Pa3X 76 produced from April 2012 (serial numbers starting from 5108 as the last four digits) plus the following serial numbers for Pa3X 76 were fixed before leaving the factory, and do not need a replacement battery:

3144, 3145, 3147, 3148, 3149, 3150, 3151, 3215, 3218, 3219, 3220, 3221, 3222, 3223,
3224, 3225, 3229, 3249, 3250, 3251, 3252, 3253, 3254, 3255, 3256, 3257, 3258, 3259,
3260, 3261, 3262, 3263, 3264, 3265, 3266, 3267, 3268, 3269, 3270, 3271, 3272, 3273,
3274, 3275, 3276, 3277, 3278, 3279, 3280, 3281, 3282, 3283, 3284, 3285, 3286, 3287,
3288, 3289, 3290, 3291, 3292, 3293, 3294, 3295, 3296, 3297, 3298, 3299, 3300, 3301,
3302, 3303, 3304, 3305, 3306, 3307, 3308, 3309, 3310, 3311, 3312, 3313, 3314, 3315,
3316, 3317, 3318, 3319, 3320, 3321, 3322, 3323, 3324, 3325, 3326, 3327, 3328, 4189,
4190, 4191, 4192, 4725, 4728, 4738, 4739, 4740, 4741, 4742, 4743, 4744, 4745, 4746,
4748, 4753, 4761, 4763, 4764, 4765, 4766, 4767, 4768, 4769, 4770, 4771, 4772, 4781,
4789, 4931, 5003, 5008, 5030, 5031, 5032, 5033, 5034, 5035, 5036, 5037, 5038, 5039,
5040, 5041, 5042, 5043, 5044, 5045, 5046, 5047, 5048, 5049, 5050, 5051, 5052, 5053,
5054, 5055, 5056, 5057, 5058, 5060, 5061, 5062, 5063, 5064, 5065, 5066, 5067, 5068.
5069, 5070, 5071, 5072, 5073, 5074, 5075, 5076, 5077, 5078, 5079, 5080, 5081, 5082,
5083, 5084, 5085. 5086, 5087, 5088, 5089, 5090, 5091, 5092, 5093, 5099, 5100, 5101,
5103, 5104, 5105, 5106, 5107,

Pa3X 61 produced from April 2012 (serial numbers starting from 5380 as the last four digits) plus the following serial numbers for Pa3X 61 were fixed before leaving the factory, and do not need a replacement battery:

5043, 5044, 5045, 5046, 5047, 5049, 5050, 5051, 5158, 5162, 5195, 5202, 5203, 5205,
5207, 5208, 5209, 5210, 5211, 5281, 5282, 5285, 5286, 5287, 5288, 5289, 5290, 5291,
5292, 5293, 5294, 5295, 5296, 5309, 5310, 5311, 5312, 5313, 5314, 5315, 5316, 5317,
5318, 5319, 5320, 5321, 5322, 5323, 5324, 5325, 5327, 5328, 5329, 5331, 5347, 5367,
5368, 5369, 5370, 5371, 5372, 5374, 5375, 5376, 5378, 5379

Thanks,
-Rich
_________________
Richard Formidoni
Technology Product Manager
Korg USA, Inc.

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