why i get mysql table crash which has only abt 30 records ?

some of the fields has collation latin1_swedish_ci and some has utf8_general_ci

does it make any difference ?

Code:
REATE TABLE `articles` (
 `id` int(11) NOT NULL AUTO_INCREMENT,
 `a_title` varchar(255) NOT NULL,
 `a_description` varchar(400) NOT NULL,
 `a_content` text NOT NULL,
 `a_views` int(11) NOT NULL DEFAULT '0',
 `a_thumbnail` varchar(255) CHARACTER SET latin1 NOT NULL,
 `a_image` varchar(255) CHARACTER SET latin1 NOT NULL,
 `a_image_caption` varchar(400) NOT NULL,
 `a_audio` varchar(250) CHARACTER SET latin1 NOT NULL,
 `a_audio_caption` varchar(300) NOT NULL,
 `a_video` varchar(650) CHARACTER SET latin1 NOT NULL,
 `a_video_caption` varchar(250) NOT NULL,
 `a_channel` enum('news','tv','979','1036') CHARACTER SET latin1 NOT NULL,
 `a_grouping` varchar(16) NOT NULL,
 `a_status` enum('active','inactive') CHARACTER SET latin1 NOT NULL,
 `a_breaking` enum('true','false') CHARACTER SET latin1 NOT NULL,
 `a_hot` enum('true','false') CHARACTER SET latin1 NOT NULL,
 `a_category_id` int(11) NOT NULL,
 `a_featured` enum('true','false') CHARACTER SET latin1 NOT NULL,
 `a_tags` varchar(50) NOT NULL,
 `a_author` varchar(120) NOT NULL,
 `a_date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
 PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=73 DEFAULT CHARSET=utf8