Beacons do not activate whenever powered and an ingot is inserted.
(More Information in the attached file.)
(Sorry for the horrible video quality, the 10mb restriction got to me 😛)
Environment
Minecraft Version: 14w32a
Operating System: Windows 8 (amd64) version 6.2
Java Version: 1.7.0_60, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 237730128 bytes (226 MB) / 455610368 bytes (434 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 62, allocated: 13, tallocated: 95
Launched Version: 14w32a
LWJGL: 2.9.1
OpenGL: AMD Radeon HD 7660D GL version 4.4.12874 Compatibility
Profile Context 14.100.0.0, ATI Technologies Inc.GL Caps: Using GL 1.3 multitexturing.
Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [NoBlur1_0.zip]
Current Language: English (US)
Profiler Position: N/A (disabled)
Didn't watch the video, but sounds exactly like MC-59533