hostapd version 1:1.0-2ubuntu5 i386

[ph35sm at free.fr]

Hello,

Five days ago, I just updated my linux ubuntu server (12.10) to the latest packages. The last time before was 125 days ago.
Got a problem with the following symptom:  after around two days, wifi seems not working, in fact I noticed that pinging from the server (where the wifi card runs) a client (for example my laptop) get high pinging times, about 5000 ms and more.
The bad solution I used up to now is : 
  killing hostapd and restart it. It works. However I am not satisfied with that :-( 
any help ? or what I should trace to help ?

Thanks.
Happy Christmas &  Kind regards - Phil

PS1: I used hostapd since 2003 :-) 
PS2:02:0a.0 Network controller: Atheros Communications Inc. AR5416 Wireless Network Adapter [AR5008 802.11(a)bgn] (rev 01)
	Subsystem: Atheros Communications Inc. Device 3071
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping- SERR+ FastB2B+ DisINTx-
	Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 168, Cache Line Size: 32 bytes
	Interrupt: pin A routed to IRQ 22
	Region 0: Memory at c0100000 (32-bit, non-prefetchable) [size=64K]
	Capabilities: [40] #80 [0000]
	Kernel driver in use: ath9k
	Kernel modules: ath9k
PS3: lsmod | grep ath
ath9k                 116549  0 
mac80211              461161  1 ath9k
ath9k_common           13783  1 ath9k
ath9k_hw              376155  2 ath9k,ath9k_common
ath                    19187  3 ath9k,ath9k_common,ath9k_hw
cfg80211              175375  3 ath9k,mac80211,ath