This probably happens because your writer does not support 12x for CD-RW. I can't be totally sure because I cannot access my 4167B at the moment to check.
The next thing you are going to ask is why since your older LG writer would support it while your 4167B does not. You are probably not going to like the answer but the truth is, CD-RW is a rather outdated format and most drive manufacturers probably don't want to waste time and effort supporting the full range of features (e.g. all possible write speeds) for it anymore. The fact is that most customers don't use CD-RW discs much anymore. However, drive manufacturers have to put CD-RW support in their drives because other drive manufacturers are doing so. If they don't, their drives will look like it has less feature and customers will not buy. So what they do is to put in CD-RW support, but not for all formats. They will support the fastest and latest format for CD-RW though (32x) but every other speed is not really that important to them.
As for why your older LG writer supported 12x, it is simple : a short time back CD-RW discs were still more important, so they included better support for it. Now it is less important.
Just burn those discs at 10x. The discs are rated as 12x max speed anyway, so it is not as if burning at 10x will damage the discs. Besides, it is only a few seconds difference in burning time between 10x and 12x. Is it really worth getting all worked up over a few seconds? Life is too short to bother about such trivial things