BSOD whilst watching Twitch.tv streams

Hello,

I was wondering if someone here could help me out. I've been having various BSOD's whilst watching gaming streams on twitch.tv. The BSOD's do not happen on launch, but after the stream has been playing for some time. They also ONLY happen whilst watching a stream. They do not occur doing any other memory intensive activity. I'm a bit perplexed why this is happening.

I've used a program called BlueScreenViewer to look into the problem. I've had the following error messages:
PAGE_FAULT_IN_NONPAGED_AREA (3 BSOD's).
IRQL_NOT_LESS_OR_EQUAL (2 BSOD's).
KERNEL_MODE_EXCEPTION_NOT_HANDLED (1 BSOD).
BAD_POOL_HEADER (1 BSOD).

Apparently all of these BSOD's have been caused by ntkrnlpa.exe (NT Kernel & System) and halmacpi.dll (Hardware Abstraction Layer DLL).

I've also ran a program called memtest86 3 days ago. This actually did pick up on many memory errors during Test #6, the Block Test. I then proceeded to remove what I thought was the faulty memory. Memtest86 then passed the Block Test. I thought the problem had been resolved, as I had not received a BSOD at all following this. However, I have just now received yet another BSOD 3 days later and it seems the problem has returned.

EDIT: I have just ran memtest86 once again. The errors have now returned. I got 6000 errors on Test #6 (Block Move Test), 3000 errors on Test #8 (Random number sequence) and 1 error on Test #9 (Modulo 20, Random pattern).

I've attached the minidump files.

Any ideas?