Logo image caching

[millers]

Hi folks - using 1.4.17 with a small inventory of products and some (slightly heavy) category and product images. With caching and compression enabled, pages load very quickly and all seems well. However, the shop logo image (/img/logo.jpg) whilst heavy-ish (I think around 14K) does not appear to be caching and is always the slowest part of any page to load.

Any thoughts on applying PS caching to the logo image or perhaps editing its "height" and "width" attributes to improve performance??

Any wisdom appreciated.