Weird Yosemite Sleep Behavior Since upgrading to Yosemite, I am having weird issues with sleep mode on my MacBook (mid-2011). Whenever my MacBook goes to sleep, it begins beeping (similar to POST codes on PCs) every 1-2 seconds, and I am forced to do a hard reset. This does not seem to happen when I am not connected to a peripheral monitor (Dell 21" monitor, and DVI adapter), however. Is this a known issue with Yosemite?

EDIT: Sometimes, this happens even without being connected to the monitor. The MacBook just goes into sleep mode, and begins beeping. Only a hard reset remediates the issue. Can someone provide me with a documented cause of this issue, and a fix?

EDIT 2: I've been fiddling with this for weeks, and I still do not know what the root cause is. I've used alternate profiles, eliminated the sleep image (per suggestion below), removed items from startup, and I still get this persistent behavior. Sometimes, after I do the hard reset, the Mac will not start back up after several attempts, but usually does after some time. I have done a hardware test, had it bench tested at a local Apple repair store, and tested the SSD for issues. None seem to be present. None of this happened until I upgraded to Yosemite. I'm out of ideas on this one. Hopefully, someone else has had this experience and can point me in the right direction.
EDIT:Make sure that you save everything you want before doing this

Try changing the hibernate mode to RAM only, run this Terminal command:

sudo pmset -a hibernatemode 0


And, try deleting the sleepimage. From /private/var/vm/sleepimage.

Do:

sudo rm /private/var/vm/sleepimage


Then type your password.