Jquery – Nivo slider enlarging images issue

While using Nivo Slider it enlarges my images to about 2x their original size which results in horrible looking pictures. I was wondering if their was a way to fix this. My image sizes are 367 x 246 px.

Here is a screen of what happens:

Here is my HTML with some ERB:

<div class="slider-wrapper up-nivo">
  <div id="slider" class="nivoSlider">
    <%= image_tag "logo.JPG", alt: "" %>
    <%= image_tag "line.JPG", alt: "" %>
    <%= image_tag "game.JPG", alt: "" %>
    <%= image_tag "leaders.JPG", alt: "" %>
    <%= image_tag "crowdFacingJim.JPG", alt: "" %>
    <%= image_tag "band.JPG", alt: "" %>
  </div>
</div>

Then here is my css:

.nivoSlider {
    position:relative;
    width:100%;
    height:auto;
    overflow: hidden;
}
.nivoSlider img {
    position:absolute;
    top:0px;
    left:0px;
}
.nivo-main-image {
    display: block !important;
    position: relative !important; 
    width: 100% !important;
}

/* If an image is wrapped in a link */
.nivoSlider a.nivo-imageLink {
    position:absolute;
    top:0px;
    left:0px;
    width:100%;
    height:100%;
    border:0;
    padding:0;
    margin:0;
    z-index:6;
    display:none;
}
/* The slices and boxes in the Slider */
.nivo-slice {
    display:block;
    position:absolute;
    z-index:5;
    height:100%;
    top:0;
}
.nivo-box {
    display:block;
    position:absolute;
    z-index:5;
    overflow:hidden;
}
.nivo-box img { display:block; }

/* Caption styles */
.nivo-caption {
    position:absolute;
    left:0px;
    bottom:0px;
    background:#000;
    color:#fff;
    width:100%;
    z-index:8;
    padding: 5px 10px;
    opacity: 0.8;
    overflow: hidden;
    display: none;
    -moz-opacity: 0.8;
    filter:alpha(opacity=8);
    -webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
    -moz-box-sizing: border-box;    /* Firefox, other Gecko */
    box-sizing: border-box;         /* Opera/IE 8+ */
}
.nivo-caption p {
    padding:5px;
    margin:0;
}
.nivo-caption a {
    display:inline !important;
}
.nivo-html-caption {
    display:none;
}
/* Direction nav styles (e.g. Next & Prev) */
.nivo-directionNav a {
    position:absolute;
    top:45%;
    z-index:9;
    cursor:pointer;
}
.nivo-prevNav {
    left:0px;
}
.nivo-nextNav {
    right:0px;
}
/* Control nav styles (e.g. 1,2,3...) */
.nivo-controlNav {
    text-align:center;
    padding: 15px 0;
}
.nivo-controlNav a {
    cursor:pointer;
}
.nivo-controlNav a.active {
    font-weight:bold;
}

Here is the css for my theme:

.up-nivo .nivoSlider {
    position:relative;
    background:#fff url(loading.gif) no-repeat 50% 50%;
    margin-bottom:50px;
    -webkit-box-shadow: 0px 1px 5px 0px #4a4a4a;
    -moz-box-shadow: 0px 1px 5px 0px #4a4a4a;
    box-shadow: 0px 1px 5px 0px #4a4a4a;
}
.up-nivo .nivoSlider img {
    position:absolute;
    top:0px;
    left:0px;
    display:none;
}
.up-nivo .nivoSlider a {
    border:0;
    display:block;
}

.up-nivo .nivo-controlNav {
    text-align: right;
    padding: 20px 0;
    line-height: 0;
    font-size: 0;
    color: transparent;
    margin-right: 2.5%;
    margin-top: -5%;
}
.up-nivo .nivo-controlNav a {
    display:inline-block;
    width:16px;
    height:16px;
    background:url(bulletFull.png) no-repeat;
    text-indent:-9999px;
    border:0;
    margin: 0 2px;
}
.up-nivo .nivo-controlNav a.active {
    background:url(bulletEmpty.png) no-repeat;
}

.up-nivo .nivo-directionNav a {
    display:block;
    height:80px;
    width:75px;
    text-indent:-9999px;
    border:0;
}
.up-nivo a.nivo-nextNav {
    background:url(arrowRight.png) no-repeat;
    background-position: 50% 50%;
    right:15px;
}
.up-nivo a.nivo-prevNav {
    background:url(arrowLeft.png) no-repeat;
    background-position: 50% 50%;
    left:15px;
}

.up-nivo .nivo-caption {
    font-family: Helvetica, Arial, sans-serif;
}
.up-nivo .nivo-caption a {
    color:#fff;
    border-bottom:1px dotted #fff;
}
.up-nivo .nivo-caption a:hover {
    color:#fff;
}

.up-nivo .nivo-controlNav.nivo-thumbs-enabled {
    width: 100%;
}
.up-nivo .nivo-controlNav.nivo-thumbs-enabled a {
    width: auto;
    height: auto;
    background: none;
    margin-bottom: 5px;
}
.up-nivoault .nivo-controlNav.nivo-thumbs-enabled img {
    display: block;
    width: 120px;
    height: auto;
}

Here is the js to start nivo:

$(window).load(function() {
    return $("#slider").nivoSlider({
      pauseTime: 10000,
      directionNav: true
    });
  });