When I playing Trine 2, sometime I need to change volume or brightness via keyboard shortcuts.
If I do it, game will minimize to taskbar.

Steps to reproduce:
1/ Start Trine 2
2/ Change volume or brightness via keyboard shortcut (no matter, if in game or in main menu)
3/ Volume/brightness will be changed, but game minimizes to the taskbar

Terminal output:

( I started the game, changed volume, changed brightness and exited game)

mattyy1hp@mattyy1hp-laptop ~ $ steam
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
unlinked 0 orphaned pipes
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
[1231/212953:WARNING:proxy_service.cc(646)] PAC support disabled because there is no system implementation
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
GLError: 1282
Generating new string page texture 2: 48x256, total string texture memory is 49.15 KB
Generating new string page texture 3: 256x256, total string texture memory is 311.30 KB
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Adding license for package 2481
Adding license for package 8538
Adding license for package 7932
Adding license for package 1045
Adding license for package 16549
Adding license for package 0
Adding license for package 12517
Adding license for package 18494
Adding license for package 18639
Adding license for package 16835
Adding license for package 17250
Adding license for package 36
Adding license for package 6098
Adding license for package 2835
roaming config store loaded successfully - 3874 bytes.
migrating temporary roaming config store
ExecCommandLine: "/home/mattyy1hp/.local/share/Steam/ubuntu12_32/steam"
Generating new string page texture 71: 128x256, total string texture memory is 442.37 KB
Generating new string page texture 72: 128x256, total string texture memory is 131.07 KB
Generating new string page texture 73: 64x256, total string texture memory is 507.90 KB
Generating new string page texture 74: 32x256, total string texture memory is 540.67 KB
System startup time: 27.79 seconds
ExecSteamURL: "steam://open/driverhelperready"
Generating new string page texture 97: 128x256, total string texture memory is 671.74 KB
Generating new string page texture 98: 384x256, total string texture memory is 1.06 MB
Generating new string page texture 99: 256x256, total string texture memory is 1.33 MB
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Generating new string page texture 127: 128x256, total string texture memory is 1.46 MB
Generating new string page texture 130: 1024x256, total string texture memory is 2.51 MB
Game update: AppID 35720 "Trine 2", ProcID 15352, IP 0.0.0.0:0
ERROR: ld.so: object 'gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded: ignored.
ERROR: ld.so: object 'gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded: ignored.
ERROR: ld.so: object 'gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded: ignored.
ERROR: ld.so: object 'gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded: ignored.
saving roaming config store to 'sharedconfig.vdf'
roaming config store 2 saved successfully
ERROR: ld.so: object 'gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded: ignored.
nohup: redirecting stderr to stdout
Game removed: AppID 35720 "Trine 2", ProcID 15352
saving roaming config store to 'sharedconfig.vdf'
roaming config store 2 saved successfully
Game update: AppID 35720 "", ProcID 15379, IP 0.0.0.0:0
saving roaming config store to 'sharedconfig.vdf'
roaming config store 2 saved successfully
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(steam)/version(1355957371_client)
Installing breakpad exception handler for appid(gameoverlayui)/version(20121219141411_client)
Installing breakpad exception handler for appid(gameoverlayui)/version(1.0_client)
Installing breakpad exception handler for appid(gameoverlayui)/version(1.0_client)
Installing breakpad exception handler for appid(gameoverlayui)/version(1.0_client)
[1231/213122:WARNING:proxy_service.cc(646)] PAC support disabled because there is no system implementation
Game removed: AppID 35720 "", ProcID 15379
saving roaming config store to 'sharedconfig.vdf'
roaming config store 2 saved successfully

System specs:

AMD Catalyst driver 12.11 beta11
AMD Radeon HD 6470M (beta11 shows 7400M series)
Cinnamon 1.6.7

Processor Information:
Vendor: AuthenticAMD
Speed: 1400 Mhz
4 logical processors
4 physical processors
HyperThreading: Unsupported
FCMOV: Supported
SSE2: Supported
SSE3: Supported
SSSE3: Supported
SSE4a: Supported
SSE41: Unsupported
SSE42: Unsupported

Network Information:
Network Speed:

Operating System Version:
Linux Mint 13 Maya (64 bit)
Kernel Name: Linux
Kernel Version: 3.6.5-030605-generic
X Server vendor: The X.Org Foundation
X Server release: 11103000

Video Card:
Driver: ATI Technologies Inc. AMD Radeon HD 7400M Series

Driver Version:  4.2.11995 Compatibility Profile Context
Desktop Color Depth: 24 bits per pixel
Monitor Refresh Rate: 59 Hz
VendorID:  0x1002
DeviceID:  0x6760
Number of Monitors:  1
Number of Logical Video Cards:  2
Primary Display Resolution:  1360 x 768
Desktop Resolution: 1360 x 768
Primary Display Size: 13.54" x 7.60"  (15.51" diag)
                                        34.4cm x 19.3cm  (39.4cm diag)
Primary VRAM Not Detected

Sound card:
Audio device: ATI R6xx HDMI

Memory:
RAM: 3418 Mb

Miscellaneous:
UI Language: English
LANG: en_US.UTF-8
Microphone: Not set
Total Hard Disk Space Available: 593389 Mb
Largest Free Hard Disk Block: 157738 Mb

Installed software:

Recent Failure Reports:
Mon Dec 31 14:37:52 2012 GMT: file ''/tmp/dumps/assert_20121231153739_1.dmp'', upload yes: ''CrashID=bp-a53826e2-d70c-4fc2-802b-0de762121231''
Mon Dec 31 15:28:40 2012 GMT: file ''/tmp/dumps/crash_20121231162834_2.dmp'', upload yes: ''CrashID=bp-ed9dd511-6ed2-41cd-9c6a-888032121231''
Mon Dec 31 15:28:43 2012 GMT: file ''/tmp/dumps/assert_20121231162841_1.dmp'', upload yes: ''CrashID=bp-ff19cea5-23b1-4cf7-a7c8-d57bd2121231''
Mon Dec 31 15:29:34 2012 GMT: file ''/tmp/dumps/assert_20121231162931_2.dmp'', upload yes: ''CrashID=bp-75f8c1e5-4b19-44c2-9c9e-5d3952121231''
Mon Dec 31 15:31:15 2012 GMT: file ''/tmp/dumps/crash_20121231163108_1.dmp'', upload yes: ''CrashID=bp-9b0bf046-9328-4438-957d-390772121231''
Mon Dec 31 15:31:18 2012 GMT: file ''/tmp/dumps/assert_20121231163115_1.dmp'', upload yes: ''CrashID=bp-0a6bd6a9-75df-4c27-80b6-6fcd52121231''
Mon Dec 31 15:31:29 2012 GMT: file ''/tmp/dumps/assert_20121231163126_2.dmp'', upload yes: ''CrashID=bp-e5017795-bea4-47f9-ae9b-caa6e2121231''
Mon Dec 31 15:35:13 2012 GMT: file ''/tmp/dumps/crash_20121231163505_1.dmp'', upload yes: ''CrashID=bp-991b9ebf-3adf-466c-bde3-6a2e22121231''
Mon Dec 31 15:35:16 2012 GMT: file ''/tmp/dumps/assert_20121231163513_1.dmp'', upload yes: ''CrashID=bp-7fa7cb11-2fbd-48e3-a580-c427a2121231''